2A77

2A77 - P0139

Information saved in
DME

Fault code
2A77 - P0139

Fault text
Oxygen sensor after catalytic converter, ageing

Fault description
Post-catalyst oxygen sensor, ageing

Condition for fault identification
Test condition:
Engine on overrun
Terminal condition: Terminal 15
Voltage condition:
Onboard electrical system voltage ubsq > 11 V

Condition for fault memory entry
1 sec.

Action in service
- Replace post-catalyst oxygen sensor

Fault effect and breakdown warning
None
MIL lights up when fault is detected in two consecutive
driving cycles

Driver information
Warning light:
MIL ON

Service instruction
None