Fault code P0054 – a step-by-step guide to diagnosing and fixing it

Error code P0054 is displayed and the check engine light is on - what does this mean?

DTC P0054 is triggered by the OBD-II system when a problem is detected with the heating of the oxygen sensor (O2 sensor) in bank 1, sensor 2. This fault code indicates that the resistance in the heating circuit of the rear lambda sensor is too low. This code may have slightly different names for different manufacturers, but always refers to the same sensor heating circuit.

What causes can this error code have?

• Defective heater in O2 sensor bank 1, sensor 2
• Short circuit in the wiring to the lambda sensor
• Damaged plug connection on the oxygen sensor
• Defective fuse in the sensor heating circuit
• Corroded contacts in the sensor connection
• Faulty engine control unit (ECM)
• Ground fault in the sensor system

What symptoms occur in parallel with fault code P0054?

• Increased fuel consumption: The vehicle consumes more fuel than usual because the mixture control is impaired.
• Poor exhaust emission values: Increased emission values may be detected during the exhaust emissions test.
• Unsteady idling: The engine runs unevenly or rough at idle.
• Loss of power: The vehicle shows reduced engine power, especially at higher speeds.
• Check engine light: The check engine light lights up continuously or flashes.

How to fix the problem of error code P0054?

• Repairing the P0054 error code requires a systematic diagnosis and appropriate measures.
• Replace oxygen sensor bank 1, sensor 2 completely: Replace the defective lambda sensor with a new original part or high-quality replacement part, as the internal heater is usually damaged beyond repair.
• Check and repair wiring and plug connections: Check all cables to the O2 sensor for damage, corrosion or short circuits and repair or replace defective cables.
• Check and replace fuses in the heating circuit: Locate the corresponding fuse for the sensor heating circuit in the fuse box and replace it if necessary.
• Diagnose the engine control unit and replace if necessary: Have the ECM checked by a specialist workshop, as a defective control unit can also trigger this code.
• Clean and ensure ground connections: Check all ground connections of the sensor system and clean corroded contacts with contact spray.