P0139

P0139

Oxygen Sensor Aging After TWC, Bank 1 - Above Limit

Diagnostic conditions
- Engine running
- Mass air flow between 28 Kg/h and 120 Kg/h (partial load) for 2 minutes
- Oxygen sensing after TWC active (basic adaption has reached steady condition)
- No secondary air diagnosis
- No fuel tank ventilation diagnosis
- EVAP canister not highly charged
- No faults recorded in oxygen sensing or oxygen sensor

Possible cause of fault
- Oxygen sensor faulty
- DME control module faulty

Affected terminals
-

Diagnosis/troubleshooting