Failed accelerator pedal position sensor 2 inside the pedal assembly.; Worn or corroded electrical connector at the pedal assembly.; Chafed or broken wire in the sensor 2 signal circuit between the pedal and the engine control module.; Short to ground in the sensor 2 signal wire or its reference voltage circuit.; Water intrusion into the pedal assembly or footwell connector causing corrosion.; Loose or damaged engine control module connector pins at the sensor input.; Rarely, an internal fault in the engine control module itself.

DTC codes / BMW codes / P1222

P1222 · BMWPedal Position Sensor 2 Low Input

Q: What does code P1222 mean?

Pedal Position Sensor 2 Low Input. P1222 on a BMW means the engine control module has detected an abnormally low voltage signal from the second pedal position sensor inside the accelerator pedal assembly. The computer expects this sensor to produce a specific voltage range that rises and falls as the pedal is pressed, and a low input tells the module the circuit is shorted to ground or the sensor has failed.

P1222 on a BMW means the engine control module has detected an abnormally low voltage signal from the second pedal position sensor inside the accelerator pedal assembly. The computer expects this sensor to produce a specific voltage range that rises and falls as the pedal is pressed, and a low input tells the module the circuit is shorted to ground or the sensor has failed.

SystemPowertrain

Code typeBMW specific

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering (injector circuits)

Symptoms you may notice

The check engine light or electronic throttle warning light illuminates on the dashboard.
The engine may enter limp mode with severely reduced power and a maximum speed limit.
The accelerator pedal may feel unresponsive or require unusually deep travel to accelerate.
Rough or erratic idle quality may appear as the module struggles to reconcile pedal inputs.
Often no symptoms besides the warning light, especially if the second sensor fails gradually.

Common causes, most likely first

Failed accelerator pedal position sensor 2 inside the pedal assembly.
Worn or corroded electrical connector at the pedal assembly.
Chafed or broken wire in the sensor 2 signal circuit between the pedal and the engine control module.
Short to ground in the sensor 2 signal wire or its reference voltage circuit.
Water intrusion into the pedal assembly or footwell connector causing corrosion.
Loose or damaged engine control module connector pins at the sensor input.
Rarely, an internal fault in the engine control module itself.

How to diagnose and fix it

Read and record all stored and pending fault codes with a BMW-capable scan tool before clearing anything.
Inspect the accelerator pedal connector and wiring for corrosion, water damage, or loose pins.
Back-probe the sensor 2 signal wire and compare live voltage against the sensor 1 signal while slowly pressing the pedal.
Check the sensor 2 reference voltage and ground circuits for continuity and short-to-ground faults.
Perform a wiggle test on the harness while watching live pedal position data to expose intermittent faults.
Replace the accelerator pedal assembly if the sensor output is confirmed low or erratic with good wiring.
Clear codes and perform a throttle adaptation reset, then verify the fault does not return during a road test.

Why pedal sensor 2 fails before sensor 1

BMW uses two opposing pedal position sensors so the module can cross-check them, and sensor 2 often sits on a lower reference voltage that makes a short to ground easier to detect first.
A low input code does not automatically mean the pedal is bad, because a rubbed-through signal wire in the footwell or a corroded connector pin can pull the voltage down just as effectively.
Technicians who replace the pedal without checking live data often find the code returns because the real fault is a chafed harness near the steering column or kick panel.
Water leaking past the windshield cowl or from a clogged sunroof drain can reach the pedal connector and cause intermittent low inputs that only appear in wet weather.
Clearing the code without performing a throttle adaptation can leave the engine in a reduced-power mode even after the repair is complete.

Can I keep driving with P1222?

You can usually drive the car to a workshop, but expect reduced engine power and avoid highways or situations that require sudden acceleration. If the car enters limp mode or the pedal stops responding, stop driving and arrange a tow.

Tools that help

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Guidance is general and written for BMW vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.