Fault code P0222 – a step-by-step guide to diagnosing and fixing it

Error code P0222 is displayed and the check engine light is on - what does this mean?

The DTC P0222 is triggered by the OBD-II system when the control unit detects too low a voltage at the accelerator pedal sensor (Throttle Position Sensor B). This fault code indicates that sensor B of the throttle potentiometer is sending a signal below the expected range. For various manufacturers, this code may also be referred to as "Throttle/Pedal Position Sensor/Switch B Circuit Low Input".

What can cause this error code?

• Defective accelerator pedal sensor (TPS B)
• Damaged or corroded wiring to the sensor
• Loose or corroded plug connections
• Short circuit in the sensor circuit to ground
• Defective engine control unit (ECU)
• Mechanical damage to the throttle body
• Interruption in the power supply to the sensor
• Faulty ground connection

What symptoms occur in parallel with fault code P0222?

• Engine performance problems: Reduced engine power and poor acceleration because the ECU cannot interpret the accelerator pedal position correctly.
• Irregular idling: The engine idles erratically or has difficulty maintaining a stable idle speed.
• Starting problems: The vehicle is difficult to start or requires several attempts to start.
• Emergency running program: The vehicle switches to emergency running mode with severely limited power and top speed.
• Jerking when driving: Uneven fuel supply leads to noticeable jerking while driving.

How can the problem with error code P0222 be rectified?

• Repairing error code P0222 requires a systematic approach to identify the exact cause.
• Replace the sensor: Completely replace the faulty accelerator pedal sensor B and then recalibrate the system to ensure correct signal transmission.
• Repair wiring: Check all cables between sensor and control unit for damage, insulate defective areas and replace with new cables.
• Clean plug connections: Remove the plugs on the sensor and control unit, clean with contact spray and reconnect firmly to ensure an optimum connection.
• Restore the power supply: Measure the 5V reference voltage to the sensor and replace the corresponding fuse or control unit if it fails.
• Renew the ground connection: Check all ground points in the sensor circuit, clean and run new ground wires if necessary.
• Replace control unit: If an ECU defect is proven, replace the engine control unit and then have all sensors re-learned.