P0051

P0051

H02S Heater Control Circuit Low

NOTE: The diagnosis for this fault is different for models with turbo engines and models with naturally-aspirated engines.

Diagnosis/troubleshooting - all turbo models

Diagnostic conditions
- Battery positive voltage between 10 V and 16 V
- Time elapsed after engine start-up greater than 10 seconds

Possible cause of fault
- Short circuit to ground in triggering wire
- Corrosion in connector, e.g. caused by moisture in the connector, etc.
- Oxygen sensor faulty
- DME control module faulty

Affected pins
DME control module connector II, pin 13 and oxygen sensor connector ahead of catalytic converter, bank 2, pin 4.

Diagnosis/troubleshooting - all turbo models

NOTE: Do not use contact spray on the oxygen sensor plug connections as this may cause irreparable damage to the wiring (contamination of the oxygen sensor via the reference air channel).







Diagnosis/troubleshooting - all naturally-aspirated models

Diagnostic conditions
- Battery positive voltage between 10 V and 16 V
- Engine running

Possible cause of fault
- Short circuit to ground in triggering wire
- Corrosion in connector
- Oxygen sensor faulty
- DME control module faulty

Affected terminals
DME control module, connector II, pin 13 and oxygen sensor jack ahead of catalytic converter, bank 2, pin 2.

Diagnosis/troubleshooting

NOTE: Do not use contact spray on the oxygen sensor plug connections as this may cause irreparable damage to the wiring (contamination of the oxygen sensor via the reference air channel).