P1223

What it means

On BMW, P1223 means the engine control unit has seen a voltage that is too high from the second track of the accelerator pedal position sensor. The pedal sensor has two tracks that are compared for plausibility, and the signal on track 2 is above the expected range. The system usually limits engine power to protect against unwanted acceleration.

Symptoms

• Engine warning light on
• Reduced power or limp-home mode
• Poor or no response to the accelerator pedal
• Engine stuck at a fixed or raised idle speed
• Hesitation or surging when pressing the pedal
• Possible reduced-power or electronic throttle warning message in the dash

Possible causes

• Faulty accelerator pedal module with an internal fault on sensor track 2likely
• Corroded, loose or damaged pedal module connector pinslikely
• Signal wire for track 2 shorted to the supply voltage or to another live wirepossible
• Open circuit or high resistance in the sensor ground wire, which pushes the signal voltage uppossible
• Fault in the sensor supply voltage from the control unitrare
• Faulty engine control unitrare

How to diagnose

1. Read all stored and pending codes and note any other pedal, throttle or supply voltage faults
2. Check freeze frame data and clear the code to see whether it returns straight away or only under certain conditions
3. View live data for both pedal tracks and check they move smoothly and stay in proportion from released to fully pressed
4. Inspect the pedal module connector and the engine control unit connector for water, corrosion, bent or pushed-back pins
5. Wiggle test the harness near the pedal and bulkhead while watching live data for jumps
6. Measure the sensor supply voltage and ground at the pedal connector against the wiring diagram for the specific model
7. Test the track 2 signal wire for short to supply and for continuity to the control unit
8. If wiring and supply are good, test or substitute the pedal module before suspecting the control unit

How to fix

• Replace the accelerator pedal module if the track 2 signal is faulty, then carry out any adaptation or initialisation the model requires
• Clean or repair the connector terminals and secure the connector
• Repair the damaged, shorted or open wiring found in the signal, supply or ground circuit
• Restore a good ground connection if the ground is faulty
• Repair or replace the engine control unit only after all other causes are ruled out, and code or programme it as the model requires

Can I keep driving?

This code for other makes

• P1223FordPedal Demand Sensor B Circuit High Input
• P1223LincolnPedal Demand Sensor B Circuit High Input
• P1223Mercedes-BenzFuel Rack Position Sensor Y2311
• P1223MercuryPedal Demand Sensor B Circuit High Input
• P1223OtherPedal Demand Sensor B Circuit High Input

Nearby codes

• P1222BMWPedal Position Sensor 2 Low Input
• P1270BMWControl Module Self-Test Torque Monitoring