2A99

2A99 - P0131

Information saved in
DME

Fault code
2A99 - P0131

Fault text
Oxygen sensor before catalytic converter, sensor wires

Fault description
Pre-catalyst oxygen sensor, sensor wires

Condition for fault identification
Test condition:
Engine running
Battery voltage: 10.7 V..16 V
Terminal condition: none
Voltage condition:
none

Condition for fault memory entry
5 sec.

Action in service
Check wiring harness
Replace oxygen sensor in front of catalyst

Fault effect and breakdown warning
It is possible to continue driving. Because the oxygen sensor
cannot be used for closed-loop control the exhaust emissions
will exceed the official limits.
MIL lights up
Higher exhaust emissions
Increased fuel consumption
Surge

Driver information
Warning light:
MIL ON

Service instruction
None