P1000 Code in 2026: Not Ready Yet, Not Broken, and How Long Until It Clears

On a Ford-family car, P1000 says the car has not finished checking itself, in the one NHTSA record that explains it. It does not say anything is broken.

P1000 is a manufacturer-defined code, so its meaning depends on the badge. NHTSA's index record of a 2004 Ford communication for the 2002 Mercury Cougar describes it as "DIAGNOSTIC TROUBLE CODE P1000 (OBD SYSTEMS READINESS TEST NOT COMPLETE) RESETTING AFTER IT HAS ALREADY CLEARED." A 2006 Ford record, for the Mustang, Fusion, Milan and Zephyr, says "DTC P1000 MAY NOT CLEAR IN HIGH ALTITUDE CONDITIONS." On a Volvo-engined Mack truck, "P1000-00" is something else entirely, "a nuisance code" in the exhaust-fluid system. The common thread for cars, in our reading of the one index line that explains it: P1000 is the Ford family's way of saying the self-tests the emissions inspection reads, called readiness monitors, have not all run since the memory was last cleared.

We searched NHTSA's manufacturer-communication file for P1000 in every spelling, and for readiness, "not ready", monitors that will not complete, drive cycles and emissions-test failures; a second, independent search added what the first had missed. We read 328 distinct maker documents on these subjects (233 in full, 95 near-duplicates through their differences), screened 201 more that used the words in another sense, and searched the full text of another 1,433 Ford, Lincoln, Mercury, Mazda, Jaguar, Land Rover, Nissan, Infiniti and Mack documents for the code (90 had no usable text layer). P1000 appears in the text of only two documents, both Mack's. The older Ford, Mazda and Jaguar records that name P1000 exist only as NHTSA index lines, with no PDF on file; we quote them as index wording. How we read everything is in the methodology at the end.

Owners almost never write "P1000" in a federal complaint (three named it, one as "a 1000 code"), so we read every complaint from 2015 to 21 September 2026 about readiness, "not ready", drive cycles or an emissions or smog test: 1,350 in all. Every one was sorted twice, independently, by the same written rules, and the two sortings matched on 91%. 645 were about this car's readiness or test result. 116 described a car that was not ready or could not be read; 359 failed or could not pass because of the check engine light or a stored code.

By the end you will know which of five routes your P1000 is on, what each costs, which maker program we read covers your car, and the cheap cause that gets skipped when a shop quotes a part.

Claims marked 🟢 rest on a document listed in the Sources section, read in full unless marked otherwise. Owner-reported figures are what people told NHTSA, published with ODI numbers, and every complaint count here comes from the 1,350 complaints sorted twice and published.

I built PulsCar after a $380 "full diagnostic" in Phuket in 2025 led to roughly $6,000 over six months across several shops (the story is on the About page). P1000 is the opposite case: a code that looks like a problem and usually is only a waiting period, and the money gets spent when nobody explains the difference. Every claim below that rests on a document names it.

What P1000 says: the car has not finished its self-tests

Readiness, in one paragraph. An OBD-II car keeps running tests on its own emissions equipment as you drive: the catalytic converter, the evaporative (EVAP) system that holds fuel vapor, the oxygen sensors and their heaters, the EGR valve and others. Each test reports "complete" or "not complete". 🟢 Nissan's readiness bulletin NTB98-018g puts it plainly: "The SRT is used to indicate whether the engine control module (ECM) has completed self diagnosis of major emissions systems and components." SRT is Nissan's name for the readiness test; Ford's owner text calls it being "ready for I/M testing", I/M meaning inspection and maintenance, the emissions program.

Where P1000 comes in. Generic OBD scan tools show each monitor as ready or not. Ford-family computers of the 2000s also stored a code; the one NHTSA index record that explains it (2002 Mercury Cougar, 2004) describes it as "readiness test not complete". 🟢 Two Ford communications of 2001 (one for the Ranger, one listing only "Ford") and a Mazda one for the B-Series truck list P1000 among the codes a vehicle may show (NHTSA index lines, no PDF on file). A 1996 Jaguar record (index line) describes an "ENHANCED INSPECTION MAINTENANCE TEST CONCERN V12 ENGINE DTC P1000 OR P1111 ALWAYS PRESENT."

Why it is maker-specific. California's OBD rule, 🟢 13 CCR 1968.2, tells makers to use the standard codes "(e.g., P0xxx, P2xxx) whenever possible" and allows manufacturer-defined codes such as P1xxx with approval, used consistently "across a manufacturer's entire product line." The rule asks for consistency within one maker's line only, so nothing stops two makers from using the same number for different things, as Mack and Ford do.

What it does not say. 🟢 Volkswagen's readiness bulletin V011518 2023591, for TDI diesels: "There is no need to repair any vehicle system due to readiness not being set." The same bulletin warns the other way too: "Resetting the ECM will erase the readiness codes and additional driving will be required to set the readiness codes."

First: P1000, a readiness screen, or a station that cannot connect?

Three different things get called "P1000" by owners and shops, and they lead to different fixes. Many parts stores read codes for free; ask whether they also show readiness status.

The reset side of this is covered elsewhere. What clearing codes and disconnecting the battery erase, the federal rule for how many monitors may be unfinished, and what five state programs tell owners are in our guide to resetting the check engine light. This page is about the code that shows up afterwards, and about the cars that will not get ready.

The 10-minute P1000 check

1. Read every code and the readiness screen (3 minutes). P1000 alone, or with other codes? A cheap reader shows both the codes and each monitor's status; parts stores print it, as owners in our study reported with readouts such as "Emission Ready NO" and "emission ready status was no". Our scanner guide covers what the readers show. Write everything down before anyone clears anything.

2. Ask what happened last (2 minutes). A new battery, a dead battery and a jump start, a repair, a recall, a software update, or codes cleared? Any of those resets readiness. If yes, the answer is probably driving, Route 1.

3. Try the key-on test, if your manual describes it (1 minute). 🟢 Mazda's 2010 Tribute manual: "To determine if the vehicle is ready for I/M testing, turn the ignition key to the on position for 15 seconds without cranking the engine. If the service engine soon indicator blinks eight times, it means that the vehicle is not ready for I/M testing". 🟢 Ohio's E-Check sheet reports the same procedure from a 2012 Ford Focus owner's manual and says it "may apply to other models and model years Ford/Lincoln/Mercury vehicles." Other makers use other patterns; our reset guide quotes Honda's and Nissan's.

4. Check for programs by VIN (4 minutes). nhtsa.gov/recalls shows safety recalls. Emissions recalls, customer satisfaction programs and bulletins, such as Ford's 22N15, are answered by a dealer; ask by number, using the maker atlas further down.

Six P1000 situations, and which is yours

"P1000 or 'not ready' right after a new battery, a jump start, cleared codes or a repair, and the car drives normally." The memory was reset. → Route 1.

"The station says it cannot communicate with the car, or reads no vehicle information." Not readiness at all. → Route 2.

"A 2017-2019 Elantra 2.0L, a 2017-2018 Forte, a 2018-2019 RX 350, a 2010 CX-7 or Mazda6 2.5L, a 2017-2019 Jaguar Ingenium diesel, or another car named in a readiness campaign, still not ready after weeks." Software. → Route 3.

"One monitor, usually EVAP, catalyst or oxygen sensor, never finishes, and there is a stored or pending code, or a part was recently replaced." The monitor may be waiting for a repair. → Route 4.

"The check engine light is on, or a permanent code is stored." A lit light fails on its own, and some programs fail a permanent code; P1000 is the least of it. → Route 5.

"P1000-00 on a Mack truck." The SCR system's nuisance code; Mack's fix is a Tech Tool dosing test (see the maker atlas), not a drive cycle.

The P1000 price ladder, from the bottom up

Read the ladder from the top. Most of the 116 readiness complaints state no amount at all; 14 do. Three are about driving the monitors ready ($35 of fuel, and dealer quotes of $500 and $700); the rest name a diagnosis, a fault repair or software, a module or a port. The larger sums belong to cars where something else was going on: a station that could not read the car, software a maker had to replace, or a real fault behind a lit light. Of the 138 dollar figures owners gave in these complaints, 82 are quotes or estimates, 25 are bills, 21 are stated as paid and 10 give no status or were refunded; the full list is published.

The five P1000 routes, cheapest first

Route 1 · Just not ready yet: battery, cleared codes, a repair — $0 and a week of driving

What it is. Something wiped the computer's memory, and the monitors start over. Nothing failed. This is the condition the Ford P1000 index line describes.

What the documents say. 🟢 Mazda's 2010 Tribute manual: "If the vehicle's engine or transmission has just been serviced, or the battery has recently run down or been replaced, the OBD-II system may indicate that the vehicle is not ready for I/M testing." It continues: "The OBD-II system is designed to check the emission control system during normal driving. A complete check may take several days." 🟢 GM prints the same mechanism in its programming bulletins, such as N222383021: "Clearing powertrain DTCs will set the Inspection/Maintenance (I/M) system status indicators to NO." 🟢 Nissan's NTB98-018g adds that readiness also goes back to incomplete when "The ECM memory power supply is interrupted for several hours."

The drive cycle, in Ford's and Mazda's words. 🟢 Ford's 2023 owner letter for program 23B63, after a computer reprogram: "Allow the vehicle to sit for at least eight hours without starting the engine." Then, after the engine warms up, do not shut it off until "15 minutes of steady driving on an expressway / highway followed by 20 minutes of stop-and-go driving with at least 30-second idle periods." The Tribute manual gives the same cycle with "at least four 30-second idle periods" and adds: "If the vehicle is still not ready for I/M testing, the above driving cycle will have to be repeated." 🟢 Ohio's E-Check sheet suggests "drive the vehicle for at least two or three days (older vehicles may take more time) including both highway and city miles."

What the owners report. 14 complaints are sorted as a battery event with no other cause stated, and 11 as a code clear, repair or recall. Short distances sometimes worked: a 2011 Honda Odyssey owner was told "TO DRIVE IT FOR 60 MILES AT HIGH SPEED AND HOPEFULLY IT WOULD THEN PASS INSPECTION. IT DID." A brand-new 2015 Malibu, with no cause stated, failed a Massachusetts emissions test at 44 miles and passed after about 100 more. Some took much longer: a 2007 Subaru Impreza owner had driven "OVER 700 MILES AFTER BATTERY REPLACEMENT" and was told to drive 50 to 100 more non-stop, and a 2020 Honda HR-V owner reported "driven 562 miles, completed 142 warm-up cycles" with the system still not ready. Seven of the 14 battery cases say the car stayed not ready after a stated period of driving or a second visit; those belong partly to Route 4.

The cheap cause that gets skipped. The drive itself. A cold start after an overnight sit, a steady highway stretch and city driving with idles, in one trip, is what the makers' cycle asks for; short errands may never run the slow monitors. The second cheap cause is a weak battery: a car that keeps going flat keeps resetting itself, as a 2017 Subaru Outback complaint describes.

Fix it yourself. Note the date of the reset, drive the maker's cycle at least once, mix in normal driving for a few days, and check the readiness screen before you queue at the station. Keep a quarter to three quarters of a tank: 🟢 Subaru's I/M advisory 11-120-12R starts its procedure with "Ensure the fuel level in the fuel tank is between ¼ and ¾ level." and recommends half a tank.

At the shop — say this: "The battery was replaced (or the codes were cleared) on [date]. Before you diagnose anything, can you show me which monitors are incomplete and whether any code is stored or pending?"

Route 2 · The station cannot talk to the car — $0 under a program; owners report $200 to $600

What it is. The test equipment plugs into the diagnostic port and gets nothing back, or gets the wrong data. The car may be perfectly ready; it simply cannot be read.

What the documents say. 🟢 Ford's 22N15 is the largest program we read: 633,445 US vehicles, a one-time gateway module reprogram "for unlimited years of service and unlimited miles from the warranty start date of the vehicle", with an over-the-air update since August 2023 counted as an equivalent remedy. 🟢 For 2021-2022 F-150s, SSM 51411 gave technicians a temporary action while Ford worked on a fix: "Leave the engine running when performing the emissions test, even when the machine prompts to shut the engine off." 🟢 GM's N232412720 covers 2024 heavy-duty diesels whose engine computer "does not correctly provide all required data to emissions Inspection/Maintenance (I/M) testing stations", and GM's recalls N202298780 and N212345540 fix 2018 Chevrolet Equinox and Traverse 2.0L engine computers that may not respond with the correct calibration verification number, CVN, which testers check. 🟢 For some 2025 Fords, SSM 52916 puts the fault on the other side: testing equipment "that has not been updated to be compatible with the new testing protocols." 🟢 A Volkswagen tech tip, TT 97-14-02, adds a physical cause: a diagnostic connector damaged by aftermarket devices. Other makers, the same pattern. The station reads more than readiness: it checks the VIN, the calibration ID and the CVN, and a wrong answer to any of them can fail a healthy car. 🟢 BMW's SI B12 09 13: "The customer of an affected vehicle may fail to pass an I/M test due to a non-compliant 17- digit vehicle identification number (VIN)". 🟢 Acura's 2022 owner letter for the 2017-2018 NSX: the engine computer "may not output some required communication data to a generic scan tool under certain conditions". 🟢 Lexus's 22LC03: a gear shift control unit "may output incorrect or missing identification codes which may result in failure at state emissions inspections (SMOG check)", while the issue "does not have an effect on the vehicle’s performance". 🟢 GM's special coverage 24280 for 2016 Chevrolet Express and GMC Savana vans with the 6-speed automatic covers a transmission module that reports the VIN a second time, which a station "could consider" a reason for failure, "although highly unlikely".

What the owners report. 21 complaints say the station or a scan tool could not communicate with the car, and 7 more name the software that fixed it. 15 of these 28 are Fords, and the Ford models match the programs: 2020-2021 Escapes and Escape Hybrids, 2021 Bronco Sports and 2021 F-150s. In a 2021 Bronco Sport complaint, the inspector "related the failure to Ford Customer Satisfaction Program Number: 22N15"; another owner paid "$260 for a repair that should be covered" after Ford denied the claim. A 2020 Escape owner in Maryland was told "many Ford models do not connect with the computer at MD State Emissions." Two 2018 Equinox owners describe failed smog tests with no OBD communication, the population of GM's CVN recalls.

The cheap cause that gets skipped. The program. A no-communication result sends owners to diagnosis, and diagnosis costs money; a VIN check for the gateway or CVN program costs nothing. The second cheap cause is the connector itself: a loose ground or a damaged port, as a 2012 Versa complaint ("non-communicating" OBD, loose grounds) and the VW tip both describe.

At the shop — say this: "The emissions station could not communicate with the car. Before any diagnosis, is this VIN in an open program or campaign for gateway or engine-computer software, such as Ford 22N15?"

Route 3 · Software that will not let a monitor finish — $0 under a campaign; owners report quotes of $460 and a $1,968 computer

What it is. The car is driven correctly, the parts are fine, but the computer's logic never completes a test, or reports it wrongly. Only new software fixes it.

What the documents say. 🟢 Hyundai 25-01-054H (Service Campaign 968) updates the engine computer on certain 2017-2019 Elantra 2.0L cars that "may be unable to complete diagnosis of the OBD-II Fuel System Readiness Monitor." 🟢 Kia SC203 restores fuel-system monitoring on 2017-2018 Forte models built May 27, 2016 to June 27, 2018. 🟢 Lexus 20LC03 reprograms 2018-2019 RX 350 and RX 350L engine computers "FREE OF CHARGE". 🟢 Mazda 6611K and Jaguar H444 fix readiness status that is set or reported wrongly. 🟢 Mercedes-Benz LI07.16-N-075574, for Sprinter OM651 diesels: after water-pump codes P260312 or P260315, "the readiness monitor remains deactivated and self-healing is not possible", and the cure is "installing new engine control unit software."

What the owners report. 13 complaints name software or the engine computer as the cause: 6 a monitor that would not finish, and 7 a car the station could not read (counted in Route 2). A 2012 Kia Sorento owner said a dealer disconnected the battery during a recall, and the oxygen-sensor monitor never reached ready "Despite driving hundreds of miles afterward"; the owner wrote that the dealer verbally confirmed "the root cause is a software condition requiring a PCM reflash, not achievable through normal drive cycles" and gave an estimate of about $460. A 2020 Acura TLX owner failed Massachusetts inspections three times; the dealer wrote that it had "not received any updated procedures or available software updates to get these cars to store the memory for the readiness flags." A 2005 MINI's comprehensive component monitor kept reading incomplete until a dealer found an internal short in the engine computer, at $1,968.

The cheap cause that gets skipped. The campaign lookup, again. Several of these programs are emissions recalls or campaigns that dealers must do at no cost. And for Honda's high-rpm monitor, 🟢 A24040A gives a specific highway procedure (5,500 to 6,500 rpm in sequential mode for at least 10 seconds, then a steady throttle); the dealer can run it.

At the shop — say this: "This monitor has not completed after [miles] of mixed driving. Is there a software update, campaign or emissions recall for the readiness monitor on this VIN?"

Route 4 · A fault the monitor is waiting for — owners report $125 to $1,450 for diagnosis and repairs

What it is. A monitor will not run, or will not pass, because a part or a stored fault blocks it. Driving more does not help until the cause is fixed. It is one cause of a monitor that never finishes; 19 of the 116 readiness complaints name a fault.

What the documents say. 🟢 California's Bureau of Automotive Repair, quoted in our reset guide, says a vehicle may never complete a monitor until the components that let it run are diagnosed and repaired. 🟢 Nissan's NTB98-018g gives one example: if the catalyst or oxygen-sensor monitors show "INCOMPLETE" and either fuel trim is 10% or more off its target, clear the learned value and diagnose the lean or rich codes (P0171, P0174, P0172, P0175) before driving the pattern again. 🟢 GM's 15-NA-010 names the rear oxygen-sensor tests on new cars as the ones that wait. 🟢 Mercedes-Benz LI49.00-N-078608: "If any fault codes or other issues arise while attempting to complete the monitors, address the issues and per- form the necessary drive cycles to clear the faults."

What the owners report. 19 complaints name a fault behind a monitor that would not finish. EVAP leaks and valves (a 2006 Santa Fe that failed for "A SMALL VAPOR LEAK" and did not reset after weeks of driving following the first repair, a 2019 Jetta with EVAP monitors not set after seven repairs, a 2021 Silverado whose AutoZone scan showed emissions not ready with an EVAP purge-pump fault), oxygen sensors and the catalyst (a 2008 Honda Fit's catalyst monitor not ready after thousands of miles, a 2018 Traverse with an incomplete catalyst monitor and a failed converter), fuel-level sensors (2007 TrailBlazer) and wiring (rodent-chewed wires on a 2019 Pacifica). The sharpest case: a 2020 Nissan Pathfinder "repeatedly failed Indiana emissions testing because the oxygen sensor monitor would not set to 'ready,' despite multiple complete drive cycles and no check-engine light or stored fault codes"; a Nissan dealer found an upstream oxygen sensor that had "failed in a way that prevented the ECM from running the emissions monitor", at $1,450.

The cheap cause that gets skipped. The pending code. A fault that has not yet turned on the light can still stop a monitor, and a cheap reader shows pending codes. The other skipped check is the monitor's own conditions: a thermostat that keeps the engine cool, or a fuel tank that is always nearly empty or full, can keep a test from starting.

Fix it yourself. Read which monitor is incomplete and any pending codes, then match the monitor to its parts: EVAP to the cap, hoses and purge or vent valves; catalyst and oxygen sensors to the exhaust; EGR to the EGR valve and passages. Tighten or replace the fuel cap if EVAP is the holdout and the cap seal is cracked; leave the rest to a shop with a smoke machine and a scan tool.

At the shop — say this: "The [EVAP / catalyst / O2] monitor will not complete. Can you check for pending codes and the enable conditions for that monitor before replacing parts?"

Route 5 · Not readiness at all: a lit light, a stored or permanent code — the fault's own price

What it is. P1000 sits beside something bigger: the check engine light, a stored code or a permanent code. A lit light fails an OBD test on its own, and some programs, such as California's, also fail a permanent code; clearing the codes also resets the monitors, so the car shows not ready afterwards.

What the documents say. 🟢 Mazda SA-041/17: "All PCM and TCM DTCs that turn on the Check Engine Light can remain as a permanent DTC." 🟢 Ford 23B63: P2073 and P2074 on certain 2011-2012 6.7L Super Duty diesels "are unable to self-heal after the vehicle has been remedied and will remain in PCM memory as a permanent DTC", which "may cause a vehicle to fail an Inspection and Maintenance (I/M) registration test in California and Delaware"; the fix is a computer reprogram. 🟢 A Chrysler STAR case, S1908000195, notes that California's smog equipment "will ignore the PDTC’s if the vehicle has completed at least 15 warm-up cycles and has been driven at least 200 miles since it’s OBD information was last cleared." Permanent codes, PDTCs, are explained in our reset guide.

What the owners report. 359 complaints say the car failed or could not pass because of the check engine light or a stored code, and 170 more failed for another or unstated reason. These are not P1000 problems, and the code behind the light decides the route; our code index lists the guides. For the 359 light-or-code failures, owners' repair figures run from $300 to $11,000 (87 figures, median $2,000); the 170 other failures add 19 figures, up to $15,000.

The cheap cause that gets skipped. Reading the code before the test. A gas cap, a loose connector or a known software update can be the whole story behind a light.

At the shop — say this: "What is the stored code behind the light, and is there a bulletin or campaign for it on this VIN? I need it fixed and the monitors ready before [test date]."

The maker atlas: who wrote about P1000 and readiness, and what they said

Ford, Lincoln and Mercury: P1000 in the 2000s, communication and permanent codes now. 🟢 Beyond the index lines above, the Ford documents in our file from 2015 on do not print P1000; they deal with the same inspection from other angles. 🟢 Customer Satisfaction Program 22N15 covers certain 2021-2022 Bronco Sport, 2020-2021 Escape and Corsair, and some E-Series, F-650/F-750 and F-53/F-59 chassis with a Smart Data Link Connector: "the GWM may not properly communicate with Inspection and Maintenance (I/M) emissions equipment due to a GWM software concern." GWM is the gateway module between the diagnostic port and the rest of the car. 🟢 SSM 51411 says "Some 2021-2022 F-150 vehicles may not be able to communicate with some emissions testing equipment", and 🟢 SSM 52916 says some 2025 Explorer 2.3L vehicles fail to communicate "due to equipment that has not been updated to be compatible with the new testing protocols." 🟢 23B63 and 22N14 reprogram 2011-2012 6.7L Super Duty diesels whose permanent codes P2073 and P2074 may fail I/M tests (23B63 names California and Delaware), and the owner letter prints the Ford drive cycle quoted in Route 1.

Mazda: a 2001 B-Series record lists P1000; its own documents talk about readiness and permanent codes. 🟢 The 2001 B-Series record lists P1000 (index line). 🟢 Mazda's 2012 emission recall 6611K reprograms certain 2010 CX-7 and Mazda6 2.5L cars because "a readiness status code, which is used for the OBD-II Readiness Test, may be incorrectly set due to improper evaporative monitoring system programming." 🟢 Mazda's service alert SA-041/17 explains permanent codes: "The purpose of a permanent DTC is to prevent customers from clearing them by disconnecting the battery cable in order to pass a smog check." 🟢 Mazda's 2010 Tribute owner's manual carries the readiness check and drive cycle quoted below.

Mack: P1000-00 is not a readiness code. 🟢 Mack's K51117312 and KC-749: "DTC P1000-00 may come active on a chassis, either alone or accompanying other SCR system codes." The fix is a Tech Tool dosing test, and "It may be necessary to run the operation multiple times." Mack prints no description for the code.

Jaguar Land Rover: software that blocks or misreports readiness. 🟢 Jaguar's H444 recall: on certain 2017-2019 Ingenium 2.0L diesels "the Powertrain Control Module (PCM) incorrectly reports the monitor readiness status as 'not supported'" during the California smog test; Land Rover's N808 is its twin, and N409 updated software on certain Range Rover Sport models whose readiness status would not complete.

GM, Nissan, Kia, Hyundai, Honda, Toyota and Lexus: monitors that cannot finish. 🟢 GM's 15-NA-010 explains why brand-new cars can fail California's smog check: the post-catalyst oxygen sensor tests wait out a catalyst break-in, and the dealer confirms at least 400 miles of break-in driving, and California has "a Smog Inspection I/M Readiness Policy that allows only the Evaporative Monitor to not be ready on newer model year vehicles." 🟢 Kia's campaign SC203 says affected cars may have had a software update that "turned off certain fuel system monitoring functions", so the car "may fail a SMOG check". 🟢 Hyundai's 25-01-054H: certain 2017-2019 Elantra 2.0L cars "may be unable to complete diagnosis of the OBD-II Fuel System Readiness Monitor." 🟢 Honda's ServiceNews A24040A says some owners' driving may not reach the range needed to run the EGR/VVT monitor, because the VTEC "only operates above 5,350 rpm". 🟢 Lexus's 20LC03 says the RX 350's emissions software "may clear the system test results which can result in a vehicle not being able to complete emission testing/smog checks."

Mercedes-Benz, Ram and the diesels: long drive cycles. 🟢 Mercedes-Benz LI49.00-N-078608 tells Sprinter diesel technicians not to clear codes, reflash or disconnect the main battery while monitors are completing, because "Taking any of these actions will reset the readiness monitors". 🟢 Ram's STAR case S1625000004 REV. A gives diesel monitor procedures that can need many hours of engine run time. 🟢 Volkswagen's TDI bulletin above prints a 60 to 90 minute profile. These are maker procedures for their own engines only.

Monitor by monitor: what each test waits for

When P1000 or a readiness screen will not clear, the question becomes which monitor is holding out. The makers' procedures we read show that each one has its own conditions, and they are not the same across brands. These are examples from the documents for the vehicles they name; your own car's procedure is in its service information or owner's manual.

EVAP, the slowest on many gasoline cars. The evaporative test checks the fuel tank and vapor lines for leaks, and it needs time, temperature and the right fuel level. 🟢 Subaru's 11-120-12R sets EVAP readiness in three steps: drive more than 30 minutes, "Park the car for 10½ hours in an area or facility with an ambient temperature from 40° — 113°F.", then drive at a steady 55 mph "for more than 5 minutes." 🟢 Nissan's drive patterns in NTB98-018g have the owner turn the ignition off and "Add 4 gallons fuel" between two trips for some EVAP tests. 🟢 GM's bulletin notes that California's readiness policy allows only the evaporative monitor to be unfinished on newer model-year vehicles.

Catalyst and oxygen sensors, which want steady cruising and coasting. 🟢 Volkswagen's tech tip TT 01-19-03, for certain VW models with a readiness status that "will not set": accelerate to 5,000 rpm and coast to about 1,200 rpm without braking, up to five times, then hold 50 to 55 mph on cruise control "for 5 minutes or more to change Catalyst readiness." 🟢 GM's 15-NA-010, for new cars after 400 miles: "perform several deceleration maneuvers from a minimum speed of 45 mph (72 km/h) for at least 10 seconds", three to four times, ignition off, and the whole step three more times. 🟢 Subaru's general procedure ends with a steady 55 mph "for more than 3 minutes".

EGR and VVT, which may need revs most drivers never use. 🟢 Honda's A24040A explains that the VTEC system included in this monitor group only runs above 5,350 rpm, so some owners' driving never completes it.

Diesel monitors, which can take days of engine running. 🟢 Ram's STAR case S1625000004 REV. A says the particulate filter monitor "takes up to 72 hours of engine run time to complete three-time based regeneration cycles" and the NMHC catalyst monitor "up to 24 hours of engine run time". 🟢 Volkswagen's TDI profile takes about 60 to 90 minutes, and Mercedes-Benz's Sprinter procedure asks for repeated 20-minute highway runs. EPA's 2013 diesel best-practices memo (not official guidance), quoted in our reset guide, says a diesel can take eight weeks or more to run all monitors.

Continuous monitors, which are ready almost at once. EPA's 2001 guidance, quoted in our reset guide, lists three that run continuously: misfire, fuel trim and comprehensive components. A continuous monitor that stays incomplete is unusual; on the 2005 MINI in our study the dealer found a shorted engine computer.

What this means for P1000. On a Ford-family car, our reading is that P1000 should clear when the last of these finishes; the 2006 Ford record says it may not clear at high altitude. A scan tool that shows the monitors one by one tells you which conditions to drive for, and saves a week of guessing.

The coverage file: which readiness and test programs are still open in October 2026

Status is our computation from the printed terms, as of 1 October 2026.

How to use the table. Programs follow the VIN, not the owner, so a used car qualifies too. Ford's 22N15 also says customers who received the August 2023 over-the-air update do not need the gateway reprogram. A dealer's VIN lookup is the final word; the table is a list of numbers to ask about.

What 1,350 complaints about readiness and emissions tests show

How we read them. Every complaint was sorted twice, independently, by the same written rules. The two sortings matched on the category for 91% of the 1,350 complaints. They differed on the category or a flag in 176 complaints; each was settled under 23 written rules, then the agreed sortings were checked for contradictions with those rules and 105 were corrected. The sorting rules and every decision are published. A separate, independent search found 209 complaints the first search had missed, mostly "smog" used as a verb and state inspections failed by the check engine light; they were sorted the same way.

What the readiness complaints share. Of the 116 readiness complaints, 37 say a battery event, a code clear, a repair, a recall or a software update came just before; 49 say the car stayed not ready after a stated amount of driving or at two or more test visits; and 25 name a consequence beyond the test, such as a registration that could not be renewed, a ticket or a fee. Ford leads the readiness group with 23 complaints, 15 of them about the car and the test equipment not communicating, then Chevrolet with 19 and Honda with 10. These are complaint counts, not failure rates: a model with many owners in testing states will file more.

The code itself. Three complaints name P1000 or "1000 code": a 2008 Nissan Frontier ("THE NEIGHBOR CAME OVER WITH HIS CODE READER. IT SAID P1000.", after a transmission failure), a 2019 Jaguar F-Type that lists P1000 among misfire and injector codes, and a 2001 Volkswagen Jetta. None of the three is a Ford-family car, and none says what the code meant on that car.

The rest of the file. 705 complaints matched our searches but were not about this car's readiness or test result: safety-inspection failures for rust or airbags, open recalls found at an inspection, or "emissions" in another sense. They are in the published file, coded N.

What owners say they paid

Owners gave 138 dollar figures in 114 of the relevant complaints; 82 are quotes and estimates, 25 bills, 21 amounts paid, 9 not stated and one refunded test fee. One rule decided which figures count, and every exclusion is listed with its reason in our notes. The figures are published with ODI numbers.

For readiness itself, the figures are small and few. 15 figures come from the 116 readiness complaints: diagnosis charges from $125 to $400, a $35 tank of driving after a battery replacement, two dealer offers to drive the car ready ("VOLVO DEALERS WANT TO CHARGE $500 TO COMPLETE THIS SMOG TEST READINESS DRIVE CYCLE", and about $700 for a Ram ProMaster after recall work), software and modules from $260 to $1,968, repairs of $700, $979.55 and $1,450, and a $14 test fee that was refunded.

For the failed tests behind a light, the repair decides the bill. 109 repair figures, median $2,000, from a $300 oxygen sensor to a $15,000 cylinder-head quote. Diagnosis charges across all relevant complaints run from $125 to $700, median $230 (17 figures). The highest are engine and transmission work that has nothing to do with P1000.

What we did not count. Vehicle prices, payments, towing, rentals, ordinary registration fees, repairs of other faults, totals that mix in unrelated work and figures about other owners. A $600 total in "INSPECTION STICKER VIOLATIONS" is the one penalty figure we kept.

Why P1000 comes back, or never leaves

It comes back because the memory was wiped again. Every battery disconnect, code clear and computer reprogram starts the monitors over. 🟢 Ford's 23B63 owner letter asks owners to run a drive cycle after the dealer reprograms the computer. 🟢 Mercedes-Benz lists disconnecting the main battery among the actions that "will reset the readiness monitors". A car whose battery keeps going flat, or that keeps visiting a shop that clears codes, will keep showing P1000.

It never leaves because one monitor cannot finish. The reasons the documents give are software (Route 3), a fault the monitor needs fixed first (Route 4), or a monitor that needs conditions the owner rarely drives in, such as Honda's 5,350 rpm or the long steady runs in the diesel procedures. 🟢 The 2004 Ford record quoted at the top describes P1000 "RESETTING AFTER IT HAS ALREADY CLEARED", and the 2006 one a P1000 that "MAY NOT CLEAR IN HIGH ALTITUDE CONDITIONS": Ford communications on both cases are listed in NHTSA's index.

Why does P1000 keep coming back after I drive the cycle? In PulsCar's reading of the maker documents and 1,350 federal complaints, for one of three reasons. Something keeps resetting the computer: a weak battery, a shop clearing codes, or a reprogram, each of which starts every monitor over. Or one monitor cannot finish: the documents name software that turned a monitor off, left it unable to finish or misreported it (Kia, Hyundai, Lexus, Mazda, Jaguar Land Rover), a fault the monitor is waiting for (EVAP leaks, oxygen sensors, the catalyst), and monitors that need unusual driving, such as Honda's 5,350 rpm VTEC test. Or the condition is not readiness at all: a stored or permanent code. 49 of the 116 readiness complaints say the car stayed not ready after a stated amount of driving or two test visits. The fix is to read which monitor is incomplete and any pending codes before more driving, then check for a campaign.

Can you drive with P1000?

Yes, in the sense that matters for safety: in our reading of the one index line that explains it, P1000 on a Ford-family car reports unfinished self-tests, and driving is how they finish. None of the Ford-family or Volkswagen documents we read treats an unset monitor as a reason to stop driving. The legal side is separate: a car that cannot pass its emissions test may not be renewable, and 25 of the 116 readiness complaints name a consequence such as an expired registration, a ticket or a fee.

Can I drive my car with a P1000 code? In PulsCar's reading of the documents, yes, and driving is what clears it. On Ford-family cars of the 2000s, the one NHTSA index record that explains P1000 describes the readiness test as not complete, which is a status, not a fault. Volkswagen's TDI readiness bulletin says there is no need to repair any vehicle system because readiness is not set, as long as no code is stored and the light is off. The exceptions are about what sits beside P1000: a flashing check engine light, misfires, overheating, a fuel smell or a car that runs badly are reasons to stop and get it checked, whatever P1000 says. On a Mack truck, P1000-00 belongs to the exhaust-fluid system, which can limit the truck in other ways, and Mack's fix is a dosing test. Plan the driving before a test date: owners in our study needed anything from 60 miles to several hundred.

Should you buy a used car showing P1000 or "not ready"?

A not-ready car on the lot is a question, not a verdict. Monitors reset when a dealer replaces a battery, and also when someone clears codes to hide a fault. Our used-car inspection checklist explains the signs a reader shows. One owner in our study, a 2013 F-150 buyer complaining of flood damage and a returning emissions fault, wrote that the emissions code returned 170 miles after purchase, "INDICATING THAT CODE WAS RESET BEFORE MY PURCHASE."

What to ask. When was the battery replaced or the computer cleared? Will the seller let the car be driven until the monitors finish, or put the emissions test in the deal? For a 2020-2021 Escape or Corsair, a 2021-2022 Bronco Sport, or a 2021-2022 F-150, ask whether the gateway or software update was done; for a 2018 Equinox or Traverse 2.0L, whether the CVN recall was done.

Clearing P1000 before an inspection

You cannot clear P1000 into a pass. Clearing codes resets the monitors, which is the situation P1000 reports on Ford-family cars, and the federal rule and state programs we quote in our reset guide turn away cars with too many unfinished monitors. 🟢 Nevada's DMV, quoted there, says erasing codes right before a test brings an automatic rejection.

What works. Finish the monitors, then go. Check the readiness screen the day before. The federal rule lets states allow one or two unfinished monitors depending on model year; California allows only EVAP on newer gasoline cars, as GM's bulletin notes. If a test is due and the car is not ready, ask the program: Missouri's, quoted in our reset guide, allows up to 30 days beyond registration expiry to reset the monitors, and a 2017 Kia Soul owner in our study, whose fuel-system and EVAP monitors never completed, asked about a waiver.

How long after a P1000 should I wait before an emissions test? From the documents PulsCar read, about a few days to a week of mixed city and highway driving for most gasoline cars, and longer for diesels and for cars with a monitor that will not finish. Mazda's Tribute manual says a complete check may take several days and gives a drive cycle: let the car sit at least eight hours, then 15 minutes of steady highway driving and 20 minutes of stop-and-go with idle periods, repeated if still not ready. Ohio's E-Check sheet advises at least two or three days of city and highway driving after a code clear or battery disconnect. Diesel procedures from Volkswagen, Mercedes-Benz and Ram take far longer. Owners in our study reported success after 60 to 100 miles, and failure after 562, 700 and 1,200. Check the readiness screen before you drive to the station.

What a shop actually does with P1000, checkpoint by checkpoint

Checkpoint 1: the monitor screen. A shop should show you which monitors are incomplete, not just the code. At the shop — say this: "Which monitors are incomplete, and are any codes stored, pending or permanent?"

Checkpoint 2: the reset history. Battery, codes cleared, repairs or reprograms in the last weeks. If one of those explains it, the shop's advice should be to drive, not to replace parts.

Checkpoint 3: the programs. A VIN lookup for gateway, CVN, readiness-monitor software and emissions recalls, before any paid diagnosis on a communication or never-ready problem.

Checkpoint 4: the monitor's enable conditions. Fuel level, coolant temperature, outside temperature and the drive pattern the monitor needs; 🟢 Nissan's and Subaru's procedures print them.

Checkpoint 5: parts last. A part is justified when a test condemns it, as in the Pathfinder case above, not because a monitor is slow.

Three P1000 traps that cost owners the most

Trap 1: clearing the code to pass. It starts every monitor over, so the car shows not ready until it has been driven. 🟢 Mazda says permanent codes exist to stop exactly this.

Trap 2: paying for diagnosis of a communication failure. When the station cannot read the car, a VIN lookup for programs such as Ford 22N15 or GM's CVN recalls comes first; one owner in our study paid $260 for a gateway reprogram the owner says 22N15 should have covered, and another was quoted almost $600 for a new module.

Trap 3: replacing parts to make a slow monitor finish. A slow monitor is normal for days after a reset. Replace a part when a test or a code condemns it; otherwise drive, and ask about software.

Three P1000 situations, decoded

These are composite scenarios, not individual customers. Each uses only facts and price ranges already in this article.

The new battery. A Ford sedan gets a new battery, then shows P1000 and fails the emissions test as not ready. The owner drives the maker's cycle (eight-hour sit, 15 minutes highway, 20 minutes stop-and-go with idles) and a few days of normal driving, checks the readiness screen, and passes. Cost: $0 beyond the test fee owners mention, $14 to $25.

The station that cannot connect. A 2021 Bronco Sport fails because the inspector's machine cannot communicate. The owner asks the dealer for program 22N15 by VIN, gets the gateway reprogram at no cost, and retests. Owners report $200 to $600 for gateway or module work: one billed, one paid, one quoted.

The monitor that never finishes. A 2018 Elantra 2.0L is still not ready after weeks. The dealer finds Campaign 968, updates the software and asks for another week of driving. Had the cause been a part, as for the 2020 Pathfinder's oxygen sensor, owners report $125 to $1,450 for diagnosis and repairs.

The P1000 plan: 10 minutes, today, this week

10 minutes. Read the codes and the readiness screen; note what was reset and when; try the key-on test if your manual has one.

Today. If the station could not read the car, call a dealer with the VIN and ask about gateway, CVN and readiness programs. If the light is on, read the code behind it first.

This week. Drive the maker's cycle at least once and a few days of mixed driving; recheck readiness before the test. If one monitor is still incomplete after two weeks, ask for pending codes, the monitor's enable conditions and any software campaign.

Where a free sound check fits, and where it does not

P1000 is a status code with no sound. A quiet engine and a not-ready computer are the normal combination after a battery change. Where sound helps is the other side of this page: a misfire, an exhaust leak or a ticking engine behind a lit light, which a free recording check can point toward before you pay for diagnosis. If the car runs normally and the only problem is readiness, driving and the readiness screen are the tools.

Sources and documents

Every NHTSA document below was read in full unless marked "(differences)", meaning it was read through its differences from a near-identical document; the six index lines have no PDF on NHTSA's site and are quoted as NHTSA's index wording.

P1000 itself

• Mack K51117312 and KC-749 (P1000-00, SCR nuisance code)
• NHTSA index record 10008141, Ford communication 17582 (2002 Mercury Cougar; index line, no PDF)
• NHTSA index record 10019026, Ford communication 0615 (2006 Mustang; index line, no PDF)
• NHTSA index record 10011430, Jaguar communication 05214 (V12; index line, no PDF)
• NHTSA index records 619431 and 619493, Ford communications 0152 (2000-2001 Ranger) and 010502 (Ford, no model), and 620891, Mazda communication 0100801 (2000-2001 B-Series; index lines, no PDF)

Ford and Lincoln

• 22N15 gateway module reprogram for I/M testing
• SSM 51411, 2021-2022 F-150 communication with emissions testing equipment
• SSM 52916, 2025 Explorer 2.3L and the SAE J1979-2 protocols
• 22N14, 22N14 Supplement #1 and 23B63, 6.7L Super Duty P2073/P2074 permanent codes and owner drive cycle

Mazda

• 6611K emission recall, readiness status code, 2010 CX-7 and Mazda6 2.5L
• SA-041/17 permanent DTCs
• 2010 Tribute owner's manual, readiness for I/M testing and drive cycle

GM

• 15-NA-010 catalyst break-in and California readiness policy
• N222383021 (I/M status indicators reset by clearing DTCs)
• N202298780 (differences) and N212345540 (differences) CVN emission recalls
• N232412720 data to I/M testing stations

Hyundai, Kia, Honda, Lexus, Nissan, Subaru

• Hyundai 25-01-054H Campaign 968
• Kia SC203
• Honda ServiceNews A24040A (differences)
• Lexus 20LC03
• Nissan NTB98-018g System Readiness Test drive patterns
• Subaru 11-120-12R state I/M advisory

Jaguar Land Rover, Mercedes-Benz, Ram, Chrysler, Volkswagen

• Jaguar H444, Land Rover N808 (differences) and N409
• Mercedes-Benz LI49.00-N-078608 and LI07.16-N-075574
• Ram STAR S1625000004 REV. A
• Chrysler STAR S1908000195
• Volkswagen V011518 2023591 TDI readiness and TT 97-14-02, tech tip TT 01-19-03
• BMW SI B12 09 13; Acura NSX product update (10206809); Lexus 22LC03; GM special coverage 24280

Rules and state programs

• 13 CCR 1968.2, California OBD II rule, section (g)(4.4) fault codes
• Ohio E-Check, OBD readiness and drive cycle information
• Federal I/M rule, Nevada, Missouri and California program pages: see how to reset the check engine light, where they are quoted and linked

Our data

• The sorting rules and decisions · How we did it · 1,350 complaints read · Owner-reported amounts · Documents

How we did it. We searched NHTSA's manufacturer-communication file (received 2015 to September 2026) for P1000 in every spelling and for readiness, I/M, "not ready", monitors that do not complete, drive cycles with monitor or emissions wording and emissions-test failures, then an independent search added 108 documents the first had missed. We also searched NHTSA's older bulletin index files (received 1995 to 2014) for P1000, and the full text of 1,433 more Ford-family, Mazda, Jaguar, Land Rover, Nissan, Infiniti and Mack documents (90 without a usable text layer) whose summaries mention emissions or engine software. Near-identical documents were grouped and one read in full; the others were read through their differences; 201 records that used the search words in another sense (airbag readiness, battery inspection and maintenance, a driving-readiness light) were screened and listed. Complaints received from 2015 to 21 September 2026 were selected by four written regular expressions, an independent search added 209, and all 1,350 were sorted twice, independently; the method, the sorting rules and every decision are published under CC BY 4.0. Counts are complaint counts, not failure rates; dollar figures are what owners wrote, mostly quotes.

Prices verified 1 October 2026 against the owner-reported figures in complaints received through 21 September 2026; no shop price estimates are used on this page.

Technical documents verified 1 October 2026 against the PDFs on NHTSA's site, the Mazda owner's manual, Ohio's E-Check sheet and the California rule text linked above.