P0122 and P0123: Throttle Sensor, Wiring or Throttle Body?

P0122 and P0123 are codes about a voltage. A throttle opened by an electric motor, or an electronic gas pedal with no cable, carries a position sensor; the engine computer reads it as a voltage and expects it to stay inside a band. In the generic code list P0122 is the throttle/pedal position sensor "A" (the first sensor) circuit, low input, and P0123 the same circuit, high input: the signal came in too low, or too high. Chrysler prints them as "P0122 - Throttle Position Sensor 1 Circuit Low." and "P0123 - Throttle Position Sensor 1 Circuit High.", and Mazda explains its P0123 as "The TP sensor No.1 circuit was flagged as a concern by the PCM indicating a high voltage." Neither code says which part is at fault.

This page answers four questions: is a P0122 or P0123 the throttle position sensor, the wiring or the throttle body; why does the car go into reduced power; can you drive it; what does it cost.

What is in scope. In the generic list P0120 is the sensor "A" circuit malfunction, P0121 range or performance, P0122 circuit low, P0123 circuit high and P0124 intermittent; P0220 to P0229 are the same family for sensor "B" and "C" circuits. Makers label them differently: Lexus and Toyota print "P01201C: Throttle / Pedal Position Sensor / Switch “A” Circuit Voltage Out of Range.", Mazda prints P0123 and P0222, Chrysler lists P0122, P0123, P0222 and P0223 inside software flashes, and Volvo prints its pedal codes in seven characters (P212200, P212300 and so on). The codes where two signals disagree, P2135 for the throttle and P2138 for the pedal, belong to the P2135 page and the P2138 page. A throttle motor fault (P2101, P2111, P2112) belongs to the P2101 page; prices are in the throttle body guide.

Which codes the papers actually tie. In the carmaker papers we read, P0122 is printed in 19 maker files and P0123 in 22: P0122 in 16 Chrysler flash files (nine bulletin numbers), two Ford bulletins and one Mazda bulletin; P0123 in the same 16 Chrysler files and six Mazda bulletins. No Toyota, Lexus, Mercedes, BMW, Nissan, Honda, GM, Land Rover, Volvo or Infiniti paper we read prints either code, and neither do the recall filings. No paper we read prints the five-character P0120 or P0124; Toyota and Lexus print P01201C (our reading: the seven-character form of P0120).

What the page rests on. The papers listed under Sources, and 1,320 federal owner complaints received from January 2015 through early October 2026, of which 1,118 describe a throttle or pedal position-sensor fault and 202 do not. Only 19 of the 1,118 complaints quote P0122 or P0123 themselves; the rest describe the sensor, the reduced power or the stall in words, so read every count as "complaints that describe a throttle or pedal sensor fault", never as "P0122 complaints". The generic label "throttle/pedal" covers either sensor; which one your car's code means is in the maker's code list, and the Chrysler, Mazda CX-9 and Mazda6 papers that print P0122 or P0123 call it a throttle position sensor (our reading). Counts are complaints, not cars; nothing is a failure rate.

Is a P0122 or P0123 usually a bad throttle position sensor, and should the sensor be the first part you buy? PulsCar read the repair papers and 1,320 owner complaints, 1,118 of which describe a throttle or pedal position-sensor fault. The papers that print the codes are mostly Chrysler software flashes and Mazda harness repairs; Toyota and Lexus print P01201C (our reading: the seven-character form of P0120) and fix it with software or, on some models, a new engine computer and fuel pump together; Mercedes, BMW and Volvo blame a connector, a pin or water, and Mercedes and BMW tell shops not to replace the pedal for connector and pin faults. 57% of the complaints state no confirmed cause, the pedal assembly is the most common named repair (171), then the throttle position sensor (128), wiring or a connector (52) and a whole throttle body (43). Read every code, ask for the software level and look at the plugs before ordering any part.

🟢 marks a claim resting on a document listed under Sources; ⚪ marks a shop-price estimate from our repair guides. Every complaint count comes from the 1,320 complaints we went through; the other data files are listed under Sources. The sorting rules and how we did it are published.

Words on this page. Papers: bulletins, special coverages and recall filings; quote their numbers to the dealer. DTC: trouble code. MIL: check engine light. ECM, PCM: engine computer. TPS: throttle position sensor. APP, APS: pedal position sensor. Freeze frame: the speed, temperature and load saved when a code sets. Flash: software update. Reduced power, limp mode: the computer limits power and speed. Special coverage: a maker's free-repair program, not a recall. Relearn: teaching the computer the closed throttle position. Harness: the bundle of wires and plugs. TCM: transmission computer. SSM: a Ford note to dealers. EDK: BMW's electronic throttle. CCU: a control unit on BMW's electric cars. BEV: all-electric car. Part 573: the defect report that opens a recall. Pinpoint tests: the shop manual's step-by-step diagnostic tests.

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).

What P0122 and P0123 say: a signal outside its band, not a named part

The signal and the band. Our plain-words reading: a position sensor needs a feed, a ground and a signal wire, and the computer expects the signal voltage to move smoothly as the throttle or pedal moves. Why it got there is the question the code does not answer.

What the Mazda papers print. Mazda's bulletins for the 2011-2013 CX-9 with VINs below the one produced on May 1, 2013 (01-017/13 and the later 01-012/15) are the only papers we read that print a per-code list of what to inspect for these circuit codes, and they do it for P0123 and for P0222, the second sensor's low-side code. For the high side: 🟢 "The TP sensor No.1 circuit was flagged as a concern by the PCM indicating a high voltage." followed by a connector or terminal malfunction, "Short to constant voltage supply circuit between throttle body terminal F and PCM terminal 2AN.", signal circuits shorting each other, and "TP sensor No.1 malfunction." For the low side: 🟢 "The TP sensor No. 2 circuit was flagged as a concern by the PCM indicating a low voltage or open circuit." followed by a connector or terminal malfunction, a short to ground, an open circuit and "TP sensor No. 2 malfunction." The sensor is last on both lists, and the harness is replaced only "If no trouble is found during the inspection above".

What you feel. 🟢 Mazda: "Some vehicles may experience a lack of power and the wrench light comes on with DTCs P0123 / P0222 stored in memory."

What it is not. It is not a two-signal disagreement (P2135, see the P2135 page; P2138, see the P2138 page) or a throttle motor fault (the P2101 page and the throttle body guide).

First: which code, which sensor, which maker label

Read the exact code before you buy anything, because the same fault family carries different labels in different makers' papers.

Your paperwork may not show the code. Most owners describe the fault with no throttle or pedal code at all. Of the 1,118 complaints, 19 print P0122 or P0123 and 37 print any code from P0120 to P0124 or P0220 to P0229, while 186 print a four-digit P2100 to P2139 code, mostly P2138 (119) and P2135 (40).

The maker atlas: who prints these codes and what they blame

Chrysler prints P0122 and P0123 in 16 files (nine bulletins and their revisions and copies), Mazda (mostly P0123) and Ford (P0122) in a few; the other makers use other labels for nearby faults, and the Mercedes entries are two-signal (P2138-type) codes, covered on the P2138 page.

The pattern. 🟢 None of the 19 files that print P0122, nor the 22 that print P0123, says to replace the throttle position sensor. They say reprogram the PCM, install a harness, repair a chafed wire, or follow normal pinpoint tests; Mazda's Tribute and 2003-2004 Mazda6 papers replace the throttle body, both only when P2135 is present. The GM papers that replace a throttle sensor, its cover or a throttle body (11273A, 14582, 13254) do it under P2135, P0121, P0221 or P16A1.

The do-not-replace lines: what the papers tell a shop to hold back

None of these says the sensor is never the cause. Each says that, for the complaint described, something comes before the part.

• Mazda 2009-2010 Tribute built June 22 to October 15, 2009 (01-007/13): 🟢 "If the vehicle only exhibits DTCs P2111 or P0122, follow normal pinpoint test diagnostics per MS3 online or Workshop Manual". The throttle body is replaced only when P2135 is present.
• Mazda 2003-2004 Mazda6 (01-015/13): 🟢 the diode cord is for codes set after a new throttle body: "Vehicles that have stored DTCs P0123 and/or P0222 without a throttle body replacement should be diagnosed and repaired according to the workshop manual, not this service bulletin."
• GM 2016-2017 CTS-V (PIP5424A): 🟢 for P0121 with P2101 and P2119 and a collapsed air filter, "Do not replace ECM, Throttle Body."
• BMW N62TU (SI B12 26 09): 🟢 "Do not replace the EDK throttle for this type of complaint."
• BMW i4, iX, i5, i7 (SIB 61 06 25): 🟢 "Note: Replacing the CCU and /or the accelerator pedal module will not eliminate this problem and is therefore not permitted."
• Mercedes-Benz models 213 and 238 (LI54.18-P-067550): 🟢 "Please do not replace any other components (e.g. accelerator pedal sensor)."
• Toyota Camry 2018-2019 (T-SB-0044-24): 🟢 "The ECM (PCM) should NOT be replaced as part of the Repair Procedure."

The 10-minute check

1. Write down when it happens (2 minutes). Cold start or freezing weather? Right after start-up? After rain, a wash or water in the footwell? After a throttle body job, a battery change, a recall or a software update? (Toyota and the Lexus ES 250 print freezing temperatures, the Lexus RX 350 start-up, Mazda a new throttle body.)

2. Read every code, with the freeze frame (2 minutes). The codes in these papers sit in lists. 🟢 Chrysler asks the shop to "verify all related systems are functioning as designed" and to repair other stored codes before the flash. If P2135 or P2138 is stored, that is the P2138 page; if P2101, P2111 or P2112 is, it is the throttle motor.

3. Look at the plugs and the harness (3 minutes). Key out, engine cold: the plug on the throttle body and the plug at the pedal, bent or pushed-out pins, green or white crust, water. 🟢 Ford's 18-2062 tells the shop to "Visually inspect the engine harness for chafing against the intake manifold, near the throttle body." Do not pull on wires or pick at pins (our advice).

4. Think back (2 minutes). A new throttle body that brought P0123 or P0222 afterwards is Mazda's noise story; a battery job, a recall or a flash in the weeks before is a software and relearn story (Route 3).

5. Run the VIN (1 minute). At nhtsa.gov/recalls, and with a dealer for bulletins, campaigns and warranty software updates, which may not show up there.

Six P0122 and P0123 situations, and which is yours

"A Challenger, Charger, 300, Grand Cherokee or Durango with the light on and P0122, P0123, P0222 or P0223." A Chrysler flash, if your engine and build date are in the paper. → Routes 1 and 3.

"A 2011-2013 Mazda CX-9 with lack of power, a wrench light and P0123 or P0222." A harness (the Mazda6 paper mentions only the light); a car in reduced power follows our safety rule above first. → Route 2.

"A Camry, Avalon, RAV4, ES 250 or RX 350 with the light on in freezing weather or right at start-up, P01201C." Software, or a new computer and fuel pump together. → Routes 1 and 3.

"A Mercedes or BMW with a driver-assist or drivetrain message, or a Volvo XC40 BEV with pedal-signal trouble, with or without a loss of power." A connector, a pin or water (a car in reduced power follows our safety rule above first). → Routes 1 and 2.

"A 2006-2010 Infiniti M35 or M45 that slows into limp-home mode." A recall on the pedal assembly (a car in reduced power follows our safety rule above first, and Infiniti's letter says not to keep driving with the light on). → Routes 1 and 4.

"Any other car with reduced power, a throttle or pedal sensor story and a code you have not read." Read every code first (a car in reduced power follows our safety rule above first). → Routes 2, 4 and 5.

The P0122 and P0123 price ladder, from the bottom up

How much does it cost to fix P0122 or P0123, and when is the sensor the wrong first purchase? PulsCar took every dollar figure in the 1,118 complaints that an owner tied to a throttle or pedal job: 93 figures in 82 complaints, 55 of them bills or amounts paid. A diagnostic fee runs $100 to $500 with a median of $150, a pedal $35 to $900 with a median of $340, a throttle position sensor $40 to $1,500 with a median of $400, a throttle body $88 to $1,400 with a median of $565, and three computer bills from $1,009 to over $2,000. Our guides carry $100 to $400 for a pedal assembly and $300 to $800 for an electronic throttle body. A recall, special coverage or warranty flash costs $0, so the VIN and the software level come before any part.

The five routes, cheapest first

Each route is a place the signal can be lost or misjudged, ordered by what it costs to rule out. "Came back" means the owner says the same fault returned.

Route 1 · A free repair: a recall, a special coverage or a warranty flash — $0 when it applies

What it is. The maker has printed a fix for a car like yours, paid by a recall, a coverage or the warranty. Whether it still applies to your car is in the coverage file below.

What the documents say.

• 🟢 Toyota and Lexus, P01201C. "The Engine Control Module (ECM) (SAE term: Powertrain Control Module/PCM) logic and the fuel pump assembly have been modified to address these conditions." The repair is an ECM and a fuel pump assembly together, 1.2 hours (T-SB-0005-24 and L-SB-0007-24); an ECM reflash only, 1.1 or 0.7 hour, on the 2018-2019 Camry (T-SB-0044-24); a reflash, 0.7 hour, on the RX 350 (L-SB-0042-19). The coverage: "This warranty is in effect for 96 months or 80,000 miles, whichever occurs first, from the vehicle’s in-service date."
• 🟢 Infiniti 13V-430, 2006-2010 M35 and M45. The cause: a sideways load on the pedal can lower the contact pressure inside the pedal position sensor. The remedy: "The accelerator pedal assembly will be replaced and the ECM will be reprogrammed at no charge to customers for parts or labor." Labor is 1.2 hours.
• 🟢 Infiniti 14V-583, certain hybrids. No code is printed and no sensor is blamed; the fault is a software error when a lost throttle sensor signal returns, and "Nissan will reprogram the ECM, at no charge for parts and labor, to correct the issue."
• 🟢 Volvo 22V-288, 2021-2022 XC40 BEV. NHTSA's summary of the recall: "Water may enter the cable harness, corroding the accelerator pedal sensor (APS) circuit." "Dealers will inspect for corrosion, install a cable splice to prevent water intrusion and, as necessary, replace the connector terminal and APS, free of charge."
• 🟢 Seven of the nine Chrysler flashes are "Reimbursable within the provisions of the warranty." Outside the warranty the papers promise nothing (our reading). 18-098-16 and 21-029-16 print "Information Only." and say the Grand Cherokee symptoms (2015 and 2014, 6.4L) that relate to the bulletin are included within recall RC-S27-16, with a PCM part-number check under the S27 service action. NHTSA lists S27 as the 2016 recall 16V-240: a free software update for a gear-selector warning on 2014-2015 Grand Cherokees built July 16, 2012 to December 22, 2015, and certain 2012-2014 Chargers and 300s. The papers do not say it fixes throttle codes.
• 🟢 GM's throttle sensor coverages have a code gate that P0122 and P0123 do not meet. 14582 starts with "With a scan tool, verify that DTC P2135, P0121 OR P0221 is set as Current or in History." and 11273A with P2135; the pedal coverages are on the P2138 page.

What the owners report. 175 of the 1,118 complaints mention a recall, special coverage or bulletin about the fault (16%), and 50 of those say the problem came back; 81 of the 175 are Chevrolets. A 2011 Impala owner: "WE RECEIVED A RECALL LETTER FOR THE THROTTLE POSITION SENSOR. THE DEALER DID NOT REPAIR IT BECAUSE THEY COULD NOT REPRODUCE THE ERROR."

The cheap cause that gets skipped. The VIN lookup and the software level. A dealer can compare the software with the latest and run the VIN against open recalls, campaigns and coverages.

Fix it yourself. The lookup only. A flash needs the maker's tool and a charger that holds the battery voltage (Chrysler asks for 13.2 to 13.5 volts, Lexus 13.5).

At the shop — say this: "Please run my VIN for any recall, special coverage or software update that names a throttle or pedal position sensor, P0122, P0123 or P01201C on this engine, and write the answer on the repair order before any part is ordered."

Route 2 · The plug, the pin, the water and the wire — $0 to look; our throttle body guide adds $150 to $400 for wiring on an F-150 job, and one owner was quoted $600

What it is. The sensor may be fine and the signal is lost or corrupted between it and the computer: a connector, a terminal, a chafed or mis-routed harness, water, corrosion, electrical noise. This is where the printed causes for P0122 and P0123 are, in the Mazda and Ford papers; Mercedes, BMW and GM print their own pedal codes or none.

What the documents say.

• 🟢 Mazda 2011-2013 CX-9 (01-012/15). The inspection list quoted above, then, if it finds nothing, a modified emissions harness, 2.6 hours including diagnosis (2.7 on the 2011). For 01-008/13 the cause is "an abnormal electrical noise within the engine harness of certain vehicles", cured with a diode harness, 0.4 hour on the CX-9 and the 2011-2013 Mazda6. The 2003-2004 Mazda6 paper (01-015/13) names the same cause after a throttle body job: a short cord with a diode, 0.2 hour, then in its revision a harness with a diode, 0.5 hour.
• 🟢 Ford. Transit Connect: "Visually inspect the 12A581 engine harness, 25-30 cm (10-12”) below the PCM connector, for wire chafing on the transmission." (0.7 hour). Focus 2.0L: the harness crossing the intake manifold, 1.3 hours with up to four wires repaired. The Mustang's spread PCM terminal is on the P2138 page.
• 🟢 Mercedes-Benz. "The fault entry may have been caused by resistance at contacts." The repair is the connector and feed line, after every test step shows no component fault.
• 🟢 BMW. "Resistance fluctuation in the EDK harness connector is causing an interruption of the EDK signal." On the i4 Gran Coupe the first version of the pin paper asked for new contact pins where the pins were found faulty; Revision 1, which adds the iX, i5 and i7, says to unplug and replug the 12-volt connector at least three times to scrape the corrosion off, still lists the contact pins to replace if they are found faulty, and: "Parts are now no longer required." The paper carries high-voltage warnings (our advice: dealer work).
• 🟢 GM. A harness trapped under the junction block on about 300 trucks (22860): "No parts are required for this repair."

What the owners report. 52 of the 1,118 complaints end at a wire, a plug or a connector (5%), and 26 of those say the problem came back (50%); 20 are Chevrolets. A 2008 Ram 3500 owner, whose stored code was P2121, lists visit after visit at the dealer: "THEY RE-CRIMPED THE PLUG ON THE PEDAL SENSOR AND THE C130 CONNECTOR UNDER THE HOOD." and then "THAT LASTED ABOUT A MONTH AND A HALF." A plug that was only re-crimped can fail again: ask whether the terminal or connector was replaced (our advice).

The cheap cause that gets skipped. The plug itself, and the other end of the wire. A connector or terminal malfunction is the first item on Mazda's list for both circuits, and Ford's papers find a chafed wire and Mercedes's a resistance at the contacts, not a sensor.

Fix it yourself. Look, do not repair. Inspecting the plugs and the harness path with the engine off and cold is free (our advice); soldering, cutting or pushing pins is shop work, and on a BMW EV it is dealer work.

At the shop — say this: "Before a sensor or a throttle body, can you test the signal wire for a short to voltage, a short to ground or a break, as Mazda's list does, inspect both plugs and the harness where it crosses the manifold, and tell me whether a wiring bulletin exists for my VIN?"

Route 3 · Software and relearn — $0 under warranty, ⚪ $0 to $200 for a flash outside it

What it is. The sensor and the wiring are sound, but the computer's logic sets or keeps the code, or a part was changed and the computer was never taught the new closed position.

What the documents say.

• 🟢 Chrysler. The flashes print the codes among many and one repair, in seven papers "Reprogram the PCM with the latest software." (three say "latest available software"); 21-029-16 reprograms both the PCM and the TCM and asks for a transmission drive learn. No cause is printed.
• 🟢 Lexus RX 350 and RX 350L. "may exhibit a MIL ON condition with DTC P01201C", "occurring within 5 seconds of engine start time", fixed by an ECM reflash because the logic "has been modified to reduce the possibility of these conditions".
• 🟢 Nissan. Its NTB21-080 paper (P0223, P0507, P2135) describes a lit light with "There are no drivability concerns." (NTB23-021, for P212B, says "No drivability issues are present."), and afterwards: "When reprogramming is complete, you will be required to perform Throttle Valve Closed Position, Idle Air Volume Learning, Accelerator Closed Position and DTC Erase."
• 🟢 GM. For P0121 and its list, carbon (PIP4578B; the repair is a cleaning and an idle learn reset). After a throttle sensor cover: "Perform the Throttle Learn Reset Procedure."

What the owners report. Software or a campaign alone is how 10 of the 1,118 complaints end, and a cleaning or relearn alone 6: 16 in all, about 1%. At least 18 mention a throttle cleaning and 13 of those say the problem came back; at least 10 mention a relearn and 6 say the same. Cleaning stories are often second visits: read them as histories, not a failure rate.

The cheap cause that gets skipped. The history: a flash, a cleaning, a battery job or a new part in the weeks before. Nissan makes the relearn part of the job and GM ends its sensor repairs with one; a part changed without it may leave the code in place (our reading).

Fix it yourself. Not honestly. A flash needs the maker's tool, and the relearns above are scan-tool procedures with conditions. A cleaning on a cool engine is within reach on some cars, with the key out, the cleaner on a rag and not sprayed into the bore, and without pushing the throttle plate open by hand (our advice); the throttle body guide carries the steps.

At the shop — say this: "Is my engine software current for my VIN, was there a flash, a cleaning or a relearn before this started, and what does the maker's bulletin list say about my code?"

Route 4 · The pedal assembly — ⚪ $100 to $400; owners report a $340 median

What it is. The sensor inside the pedal, or the pedal's own plug, really is bad. The generic label "throttle/pedal" covers either sensor, but the Chrysler, Mazda CX-9 and Mazda6 papers that print P0122 or P0123 call it a throttle position sensor; a pedal is the suspect when the maker's code list or a test of the signal points there (our reading).

What the documents say.

• 🟢 GM's pedal papers 14636 and N182188250 print P2122, P2123, P2127, P2128 and P2138, not P0122 or P0123; 16-NA-012 prints no code, only "DTCs". All three are on the P2138 page.
• 🟢 Infiniti 13V-430. The pedal assembly is replaced with a corrugated cover on the sensor harness and an ECM reprogram: "Install corrugated cover on the accelerator pedal position sensor harness." The pedal is learned afterwards: "NOTE: The pedal position learning will be done as part of the ECM reprogramming."
• 🟢 Volvo 22V-288. The pedal (APS) is replaced along with a new cable connector kit when any of nine listed codes is stored (P212200, P212300, P212700, P212800, P213800 and four others). Our reading: the five named are Volvo's forms of P2122, P2123, P2127, P2128 and P2138.
• 🟢 Mercedes-Benz and BMW forbid the pedal sensor or module for their connector faults (see the do-not-replace lines).

What the owners report. 171 of the 1,118 complaints end at a replaced pedal assembly or pedal sensor (15%), the largest named repair; 134 of them describe reduced power or a pedal that did not respond (78%), 23 a stall, and 42 say the problem came back (25%). 92 of the 171 are Chevrolets and 49 are Malibus, where GM's coverages sit; 13 are Subarus.

The cheap cause that gets skipped. The plug and the coverage. Volvo pairs the new pedal with a new connector kit, and Mercedes and BMW forbid the pedal; BMW says a new pedal module will not eliminate the problem.

Fix it yourself. Sometimes, where the pedal bolts on and the plug, harness and VIN checks have already pointed there (our advice). Where the maker prints a learn, as Infiniti does, it is a scan-tool step.

At the shop — say this: "Which test showed the pedal and not its plug or harness? Is the part a maker part with a warranty, is a pedal learn included, and is my car under any coverage that pays for it?"

Route 5 · The throttle position sensor, the throttle body or the computer — ⚪ $300 to $800 for a throttle body; owners report a $400 median for a throttle position sensor and $1,009 to over $2,000 for a computer

What it is. The throttle's position sensor sits in or on the throttle body, and on many cars it is not sold alone, so a sensor job becomes a throttle body job. A computer is the last resort, and for these circuits almost no paper replaces one.

What the documents say.

• 🟢 GM 14582. "Bosch supplied throttle bodies require that the throttle body be serviced by replacing the complete assembly." On Hitachi units a sensor cover kit comes first. GM's gate is a current or history P2135, P0121 or P0221; 11273A, gated by P2135, replaces the throttle position sensor and reprograms the ECM. For the P2135 procedure see the P2135 page.
• 🟢 GM 13254, 2014 Silverado and Sierra 5.3L. "The throttle position sensor may cause the engine to run rough, set a P16A1 DTC, illuminate the malfunction indicator lamp and/or an Engine Reduced Power message." The remedy: "Install a new throttle body assembly.", 0.4 hour, then an idle learn.
• 🟢 Mazda 2009-2010 Tribute built June 22 to October 15, 2009. With P2135: "This concern may be attributed to the Throttle Body Assembly hardware." 0.6 hour. With P0122 alone, normal pinpoint tests.
• 🟢 The computer. Chrysler's flashes reprogram it; GM's PIP5424A (a CTS-V air-filter paper) and Toyota's T-SB-0044-24 say not to replace it; Toyota's other P01201C paper replaces it with the fuel pump.

What the owners report. 128 of the 1,118 complaints end at a replaced throttle position sensor (11%); 33 of them describe a stall (26%) and 22 say the problem came back (17%); 39 are Chevrolets and 27 Fords. 43 end at a whole throttle body (4%), 12 of them with a return (28%); 18 are Chevrolets. Three owners report a computer billed from $1,009 to over $2,000.

The cheap cause that gets skipped. The harness near the throttle body and the cover kit. Ford's 18-2062 puts the chafe at the intake manifold next to the throttle body, GM's Hitachi rule puts a cover before the whole assembly, and Mazda's noise cure is a diode harness on the throttle body connector.

Fix it yourself — the honest split. On many four-cylinder engines the throttle body is a few bolts, a gasket and a plug; the closed-position relearn that follows needs a scan tool (our advice). A computer is never a driveway job.

At the shop — say this: "Did the throttle sensor signals read wrong on the scan tool, or is this a code only? Are the harness and plug checked, and is the relearn included?" For a computer, say this: "Is my engine computer under any warranty, did the shop ask the carmaker's technical hotline, and can I see the answer in writing?"

The coverage file: which recalls and programs run in September 2026

The status column is our computation from the printed terms, as of September 2026, not a promise from any maker. Most of these papers print no end date, and the VIN decides. Campaigns and emission items may not show on nhtsa.gov/recalls, so the dealer, with your VIN, is the lookup. Mercedes-Benz's pedal harness warranty extension is described on the P2138 page.

What 1,118 complaints show

We took the NHTSA owner complaints received from January 2015 through early October 2026 that name a code from P0120 to P0124 or P0220 to P0229, or describe a throttle or pedal position sensor fault in words: 1,320 in all. 1,118 describe such a fault on the owner's car; 202 do not. Another 143, whose only link was a pedal or throttle code from P2121 to P2139 (mostly P2135 and P2138), were left out because those codes have their own pages, and so were complaints that blame only a throttle body or its motor (about 3,800 complaints in the period mention a throttle body; most of those are not in the file).

The biggest line is "no confirmed cause". It holds the owners who report the event and nothing was found or done yet, the owners who only guess, and the owners who replaced a part with the problem staying and no other cause named. 288 of the 637 say the problem came back or a repair did not fix it (45%).

What the owners describe. At least 730 describe reduced power, limp mode, a wrench or reduced-power message, or a throttle or pedal that did not respond (65%); at least 211 a stall (19%); 175 mention a recall, special coverage or bulletin about the fault (16%); 422 say the problem came back or a repair did not fix it (38%). These counts are floors: of 418 narratives with reduced-power wording, 60 are flagged no, and about 15 stalls are flagged no, among them the 2016 Malibu complaint below.

Who. Chevrolet is 407 of the 1,118 (36%), then Ford 122 and Jeep 71; the Malibu (162) and the Impala (89) alone are 251 (22%). Our reading: that likely reflects GM's "Engine Power is Reduced" wording, its special coverages and the cars sold, not a ranking of makes.

The complaints that print P0122 or P0123 themselves

Only 19 of the 1,118 print one of the two codes: 10 print P0122, 12 print P0123 and 3 print both. Eleven also print P0222 or P0223 and 9 also print a four-digit P2100 to P2139 code. They end mostly with no confirmed cause: 14 state no diagnosis or repair, or a part replaced with the problem staying, 2 a wire or connector, 2 a throttle body and 1 a pedal.

A 2019 Cherokee and a 2018 Compass ended at a throttle body: the Compass owner, with P0123, P0222, P2111 and U0420, wrote that the codes "All indicated that it was the Throttle." These are owners' accounts.

What owners say they paid

93 figures in 82 of the 1,118 complaints are ones an owner tied to a throttle or pedal job: 24 amounts paid, 31 bills, 26 quotes and 12 with no status stated. They are what owners wrote, not audited invoices, and we publish them with NHTSA complaint numbers. The 55 that are bills or amounts paid run from $45 to $2,000 with a median of $500. The ranges and medians by job are in the price ladder above; the one wiring figure is a $600 quote. The groups with fewer than five figures are ranges, not typical prices.

Why P0122 and P0123 come back after a repair

Our reading of why a repair does not hold: The part was not the cause. A new sensor or throttle body on a bad plug gives the same code. Of the 481 complaints that state a finding or a repair, 134 (28%) also say the problem came back or a repair did not fix it, and wiring is highest among the groups with a real sample, 26 of 52 (50%). The connection is intermittent. The Ram 3500 owner above had the plug re-crimped, bypassed and re-crimped again. A step was left out. Nissan and GM end their sensor repairs with a learn, and Chrysler's and Lexus's papers ask for a charger that holds the battery voltage during the flash; if the relearn or flash was skipped or interrupted, the maker's steps were not completed.

Can you drive with P0122 or P0123?

Can I drive with P0122 or P0123? This is PulsCar's advice, not a maker's rule: If the check engine light is flashing, or the car is in reduced power, stalls, or will not accelerate normally: pull over safely, switch the engine off, and have it towed. The only exception, for a flashing light alone on a car that starts and runs normally, is a shop within 2-3 miles, reached gently, under 40 mph with light throttle. Never drive a car that will not start or will not respond to the pedal. Exception, 2006-2010 Infiniti M35 or M45 (recall 13V-430): follow Infiniti's letter, call an Infiniti dealer immediately and do not keep driving with the light on, steady or flashing. Why tow: at least 211 of 1,118 complaints describe a stall, and at least 75 of those mention a highway, freeway, interstate or expressway. A steady light on a normally driving car (not the Infiniti M35 or M45) is a shop visit within days.

The documents near these codes say more. 🟢 Infiniti's interim owner letter for the M35 and M45 (13V-430), sent before the remedy was ready: "you can continue operating your vehicle normally unless the Malfunction Indicator Lamp (MIL) in vehicle is illuminated", then "Do not continue using your vehicle with the MIL illuminated." For the hybrids: "Although this can be overcome by normal application of the service brakes, it could potentially increase a risk of a crash." NHTSA's summary of the Volvo recall: "A corroded APS circuit may send corrupted signals, causing unintended acceleration, a lack of acceleration, or a loss of drive power, increasing the risk of a crash." Volvo's April 28 retailer notice said "The vehicle is still controllable, and the customer can always stop the vehicle with the brake pedal.", a sentence its May 13 notice no longer carries. Mercedes lists ESP, brake assist and PRE-SAFE as unavailable and adds "The brake system continues to operate with normal effectiveness." BMW's own paper is inconsistent: its situation text says "You can continue driving. Drivetrain", its claims section names a "Drive system, stop carefully" message. If your BMW shows a message that says stop, pull over safely and call a BMW dealer. Our rule is at least as strict as the papers where they say to drive on. Only Infiniti's letter (any lit check engine light on a 2006-2010 M35 or M45) and a BMW stop message are stricter than our steady-light advice, and for those we follow the maker.

The safety side in the complaints. At least 211 describe a stall. Of those, at least 75 mention a highway, freeway, interstate or expressway (36%), 27 an intersection, a stop sign or a light (13%), 21 the steering (10%), 28 the brakes (13%) and 30 use words like "without warning" or "no warning" (14%); 74 mention restarting (35%). In NHTSA's own fields, 17 of the 1,118 are marked as a crash, 6 as a fire, 6 with an injury, 1 with a death and 26 as towed; the fields mark the complaint, not proof that the sensor caused it. One 2016 Malibu complaint describes a car that slowed from 55 to 20 mph, stalled before reaching the emergency lane and was hit by an SUV.

Should you buy a used car with a P0122 or P0123 history?

Ask what was found, not what was replaced. Ask for the invoice that names the test (every code, the software level, a look at the plugs), have a dealer run the VIN for the recalls above, and before you pay let the car sit at idle and drive it cold and warm, watching for a light or a drop in power.

Clearing P0122 or P0123 before an inspection

A cleared code comes back if the cause is still there, and many inspections need the car's self-checks to have run again after a clear; ask the station how many trips it needs. Fix first, drive several normal trips, then test; how to reset a check engine light covers the mechanics. Do not clear a code before a shop has read it: the freeze frame is the evidence.

What the papers tell a shop to do with these codes, checkpoint by checkpoint

1 · Codes and conditions: every stored code with the freeze frame, and when it happens. 2 · Software: the level and any bulletin number; on a Chrysler, a Lexus, a Nissan or an Infiniti the repair may be only this. 3 · Plugs and harness: both plugs, the pins, the harness where it crosses the manifold, and the signal wire for a short or a break. 4 · The VIN: recalls, campaigns and coverages. 5 · The part: only then a sensor, a pedal or a throttle body, with the maker's relearn.

Three P0122 and P0123 traps

Trap 1 · Buying a sensor or a throttle body from the code. No paper that prints P0122 or P0123 names a new sensor as the fix (Mazda's inspection list puts the sensor last, after the plug and the wires), and Mazda's throttle body job needs P2135. Mazda's 2003-2004 Mazda6 paper shows the reverse: a new throttle body can itself bring P0123 and P0222.

Trap 2 · Replacing the pedal on a bad plug. Mercedes and BMW forbid the pedal for their connector faults, Volvo pairs it with a connector kit, and 42 of the 171 pedal complaints say the problem came back.

Trap 3 · A cleared code or "could not duplicate" taken as a repair. 29 complaints end with a check that found nothing, and the Impala owner above was sent home because the dealer could not reproduce the error. Toyota's papers set the code in freezing weather, so a test in a warm bay may find nothing (our reading). Ask for the freeze frame and the software level on the repair order, not a clear.

The P0122 and P0123 plan: 10 minutes, today, this week

First, the safety rule. If the check engine light is flashing, or the car is in reduced power, stalls, or will not accelerate normally: pull over safely, switch the engine off, and have it towed. The only exception, for a flashing light alone on a car that starts and runs normally, is a shop within 2-3 miles, reached gently, under 40 mph with light throttle. Never drive a car that will not start or will not respond to the pedal. Exception, 2006-2010 Infiniti M35 or M45 (recall 13V-430): follow Infiniti's letter, call an Infiniti dealer immediately and do not keep driving with the light on, steady or flashing. Then, if the car drives normally, today (10 minutes). Look at the plugs and the harness path, write down when it happens and what changed first, and read every code (a parts store reads it free; ask for the freeze frame). Today (VIN). Ask a dealer to run your VIN for recalls, campaigns and software updates, and to write down the number of any that applies. This week. If the light is steady and the car drives normally (not the Infiniti M35 or M45 above), pay for one diagnosis and ask for the software level, a test of the signal wire and the plugs, and only then a part.

Three composite scenarios

These are composite scenarios, not individual customers; the dollar figures are shop-price ranges. A Dodge Charger 6.4L has the light on with P0122 and P0222 and drives normally: the owner asks the dealer to run the VIN and check for the Chrysler flash, 0.2 hour in most of its papers, before agreeing to a throttle body at $300 to $800. A 2019 Toyota RAV4 shows the light and reduced power in freezing weather with P01201C (a car in reduced power follows our safety rule above first): the owner asks for the T-SB-0005-24 check and the Federal Emission Warranty terms, 96 months or 80,000 miles from the in-service date, before any throttle part. A used 2011 Mazda CX-9 has a wrench light and P0123 with P0222 (a car in reduced power follows our safety rule above first): the owner asks for Mazda's inspection of the connector, the short to voltage or ground and the open circuit, and a diagnosis at $80 to $150, before a pedal at $100 to $400 or a throttle body.

Sources and documents

Primary documents only, dated as printed. Claims marked 🟢 rest on one of the items below; claims marked ⚪ are shop-price estimates carried from PulsCar's repair guides.

1. Chrysler: 18-045-16 Rev. A (August 5, 2016), 18-090-16 (July 22, 2016), 18-098-16 (September 2, 2016), 21-029-16 (September 1, 2016), 18-032-16 Rev. A (August 16, 2016), 18-062-17 (June 27, 2017), 18-094-16 (August 12, 2016), 18-074-15 Rev. A (December 8, 2015), 18-113-15 (December 24, 2015).
2. Mazda: 01-007/13 and 01-008/13 (February 26, 2013), 01-015/13 (June 14, 2013) and its revision (August 22, 2013), 01-017/13 (July 2, 2013), 01-012/15 (June 17, 2015).
3. Toyota, Lexus: T-SB-0005-24 (February 7, 2024; Rev. 2, April 2, 2025), L-SB-0007-24 (February 7, 2024), T-SB-0044-24 (May 10, 2024), L-SB-0042-19 (October 28, 2019).
4. Mercedes-Benz, BMW: LI54.18-P-067550 version 7 (May 27, 2022) and version 8 (December 5, 2025); BMW SIB 61 06 25 (May 28, 2025) and Revision 1 (August 31, 2026), SI B12 26 09 (December 2014).
5. Ford: 16-0163 (December 9, 2016), 18-2062 (February 19, 2018), SSM 54736 and SSM 55072 (no date printed).
6. General Motors: special coverage 14636 (April 2015), 11273A (June 2013), 14582 (September 2015), N182188250 (August 2019); 22860 (December 2015), 16-NA-012 (February 2016), PIP4578B, PIP5424 and PIP5424A (September and October 2016), PI1538 (October 2015), PIP6112 (May 2026), 13254 (August 2013 or 2014, as printed).
7. Nissan, Infiniti, Honda, Land Rover, Volvo: Nissan NTB21-080 (September 1, 2021) and NTB23-021 (March 10, 2023); Honda 13-042 (January 8, 2014, as printed); Land Rover Q431 (November 17, 2014) and SGI14-52 (December 23, 2014); recalls 13V-430 (September 26, 2013), 14V-583 (September 19, 2014) and 22V-288 (April 28, 2022), with the filings listed in the document file.

Data and method: complaints, amounts, figures left out, documents, the sorting rules and how we did it (CC BY 4.0).

Neighbouring pages: P2138, P2135, throttle body replacement cost, hesitation when accelerating, a car that won't accelerate, stalling while driving, P0505 and idle hunting after a cleaning and the check engine light. The throttle motor code P2101 has its own page.

What this page cannot tell you. Which part is wrong on your car: only a test of the signal and the plugs can. The complaint file holds cases where an owner wrote to NHTSA, in the owner's words and unverified, and owners whose trouble ended are mostly not in it, so no failure rate can be computed from it. Complaints whose only link is a pedal or throttle code from P2121 to P2139 (those have their own pages), or that blame only a throttle body, were left out. The papers are those NHTSA publishes and we could read; a maker paper that is not there is not here, and coverage status is our computation from printed terms.

Prices verified July to October 2026 in the repair guides they are carried from and in the owner reports above, and reviewed quarterly.

Technical documents verified October 2026.

Did a P0122 or P0123 clear with software, a plug, a harness or a recall? Email [email protected] with the vehicle, mileage and outcome.