P2122 The signal from accelerator pedal position sensor D (usually the first pedal sensor) is lower than its normal range

Accelerator pedal position sensor D circuit low

P2122 in short

P2122 means the signal from one accelerator pedal sensor is reading too low, usually from a short to ground, a damaged or stretched wire, a bad connector or a failing pedal sensor. Expect reduced throttle response or limp mode. If the engine suddenly loses power, drops to idle or stalls while driving, pull over safely and tow.

The accelerator pedal has two or three position sensors that report how far it's pressed. 'D' is normally the first pedal sensor. Their signals should mirror each other, and each must stay inside a voltage window.

P2122 sets when sensor D's voltage drops below that window. A wire rubbing through to ground, a pulled or damaged connection, or a worn sensor can cause it. Chrysler calls the same code 'Accelerator Pedal Position Sensor 1 Circuit Low'.

Several bulletins point at wiring rather than the pedal: Chrysler minivans with adjustable pedals had the harness clipped too tight, Ford had a poorly seated battery junction box connector, and GM found a harness rubbing the engine. FCA also warns that unplugging the pedal during diagnosis sets P2122, so confirm it's active before replacing anything.

Most likely causes

  1. Pedal sensor wire shorted to ground or damaged

    Common general cause
    Why it ranks here
    A low-voltage code points first at the circuit; KBB names a short to ground and GM found harness rubbing with P2122.
    What would change this
    Likelier if the reading changes when the harness is moved or a fuse has blown.

  2. Loose, stretched or badly seated connector

    Supported by vehicle data
    Why it ranks here
    Chrysler and Ford bulletins trace P2122 to a tight harness clip and a poorly seated junction box connector.
    What would change this
    Likelier if the code is intermittent.

  3. Failing accelerator pedal sensor

    Common general cause
    Why it ranks here
    Worn pedal sensors are a common electronic throttle fault, but FCA advises confirming the code is active before replacing the pedal.
    What would change this
    Likelier if the wiring tests good and the signal is still low.
    How to test the accelerator pedal position sensor

  4. Code set by unplugging the pedal during earlier diagnosis

    Supported by vehicle data
    Why it ranks here
    FCA notes P2122 sets if the pedal connector is disconnected during diagnosis.
    What would change this
    Likelier if the code is history-only after recent work.

What to test first

Start at step 1. Each result tells you what it means and where to go next.

  1. Read codes, note whether P2122 is active or history-only, and watch the pedal sensor readings in live data while slowly pressing the pedal

    Low riskTool: OBD-II scan tool with live data

  2. With the ignition off, look at the accelerator pedal sensor connector and the throttle body connector for corrosion, backed-out pins or harness rubbing

    Low riskTool: Flashlight

  3. Test the sensor D reference, ground and signal circuits to the service manual

    Best left to a shopTool: Digital multimeter

    Warning:Back-probing sensor and computer circuits can damage terminals or the computer; follow the maker's procedure.

Symptoms

  • Check engine light or electronic throttle warning light
  • Reduced throttle response or limp mode Gets more serious: stop and have it checked.
  • Engine suddenly loses power or drops to idle Gets more serious: stop and have it checked.

Compare with: Check engine light with loss of power

How to fix

  1. Ask a dealer whether your VIN is covered by an open bulletin or special coverage for the accelerator pedal or its wiring; GM, for example, extended coverage on some 2016-2018 Malibu, LaCrosse and Regal models.

  2. Write down when it happens (cold start, after rain or frost, at cruise, after a battery disconnect) and whether turning the engine off and on clears it. That detail helps the shop find an intermittent fault.

Parts and cost context

  • Accelerator pedal position sensor:On most cars the pedal sensors are part of the pedal assembly. Confirm the code is active and the wiring is good first. Labour varies; get a quote.

Labor varies by vehicle and shop; get a quote before you approve a repair.

Compare used part prices on PartPriceGuide

On your vehicle

Dodge

  • 2010 · Grand Caravan

    Supported by vehicle data

    With power adjustable pedals, a tight harness can set P2122; the clip is disconnected. Whether the bulletin is still current is not verified.

  • 05-001-10Status unverified

    ETC light or P2122/P2127: disconnect harness clip near the pedal sensor (adjustable pedals)

    2010grand-caravan · issued · NHTSA 10033545

    ETC light or P2122/P2127 on minivans with power adjustable pedals; the pedal sensor harness is held too tight and the clip is disconnected. Also Chrysler Town and Country.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Chrysler

  • 2010 · Town and Country

    Supported by vehicle data

    Same adjustable-pedal harness fix as the Grand Caravan. Whether the bulletin is still current is not verified.

Ford

  • 2012–2013 · Focus

    Supported by vehicle data

    A damaged or poorly seated battery junction box connector can set P2122. Whether the bulletin is still current is not verified.

  • 2013 · Escape

    Supported by vehicle data

    Same junction box connector issue as the Focus. Whether the bulletin is still current is not verified.

  • ASI-44356Status unverified

    P2122/P2127/P2138 from a damaged or poorly seated battery junction box connector

    2012–2013focus, escape · issued · NHTSA 10055021

    Damaged or poorly seated battery junction box connector setting P2122, P2127 and/or P2138.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Chevrolet

  • 2013 · Equinox

    Supported by vehicle data

    Engine harness rubbing can blow a fuse and set P2122. Whether the bulletin is still current is not verified.

  • PIT5203Status unverified

    Open fuse with P06A3 and P2122: inspect engine harness for rubbing (Equinox)

    2013equinox · issued · NHTSA 10112911

    Open 20 A fuse with P06A3 and P2122; engine harness rubbing the engine.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • P2138Two accelerator pedal position sensor signals (D and E) that should agree with each other don't

    Shares causes Supported by vehicle data

    Ford's Focus and Escape bulletin lists P2122 with P2138 from the same poorly seated connector.

  • P2135Two throttle or pedal position sensor signals (A and B) that should agree with each other don't

    Same system Possible — needs testing

    Both are position sensor faults in the same electronic throttle system.

All Electronic throttle and accelerator pedal codes

P2122 questions

Should I replace the gas pedal for P2122?

Not before checking the wiring and confirming the code is active. Several bulletins trace it to harness or connector faults, and unplugging the pedal during diagnosis can set it by itself.

Sources and review

  1. p2122 Code - Throttle/Pedal Position Sensor/Switch 'D' Circuit Low — Kelley Blue Book (KBB Service Advisor)
  2. What You Should Know About Electronic Throttle Control — AA1Car (Larry Carley)
  3. N182188250: Special coverage: accelerator pedal position sensor connection (Malibu, LaCrosse, Regal) — General Motors / NHTSA ,
  4. NHTSA recall 26V081: Electronic throttle body gears may break (2024-2025 Nissan Rogue 1.5L VC-Turbo) — Nissan North America / NHTSA ,
  5. NHTSA ODI Preliminary Evaluation PE13-003: Electronic throttle body malfunction (2009-2013 Escape, Fusion, Mariner, Milan) — National Highway Traffic Safety Administration, Office of Defects Investigation ,
  6. SB-01-045-10: P2104/P2111 with possible fail-safe speed limit (CX-9) — Mazda North American Operations / NHTSA ,
  7. PIT5203: Open fuse with P06A3 and P2122: inspect engine harness for rubbing (Equinox) — General Motors / NHTSA ,
  8. 05-001-10: ETC light or P2122/P2127: disconnect harness clip near the pedal sensor (adjustable pedals) — Chrysler Group LLC / NHTSA ,
  9. ASI-44356: P2122/P2127/P2138 from a damaged or poorly seated battery junction box connector — Ford Motor Company / NHTSA ,
  10. 9003413: Before replacing the accelerator pedal: diagnose wiring and connectors, P2122/P2127 — FCA US LLC / NHTSA ,
Last reviewed
Written by
Saurabh K.
Editorial review
Pending
Technician review
Technician review pending

This page explains what a code usually means; it is not a substitute for a professional inspection. How we source and review · Report an error

My Car

Pick your car and code pages will point out notes and bulletins for it. Saved only in this browser.

Fill this in from your VIN

Used once to identify your engine; not stored.