P2097

2C31 - P2097

Information saved in
DME

Fault code
2C31 - P2097

Fault text
Oxygen sensor before catalytic converter, trim control

Fault description
Post Catalyst Fuel Trim System Too Rich (Bank 1)

Condition for fault identification
Test condition:
Trim control I segment (precision controller with O2 sensor
behind cat.) exceeds delta lambda threshold > 0.03; mixture
(with lambda closed-loop control) too rich
Terminal condition: Engine running
Voltage condition:
battery voltage<11V oder Ubatt > 16 volts

Condition for fault memory entry
Fault monitoring criterion must remain present over 1 sec.

Action in service
1. Replace LSU;
2. Repair leak in exhaust system
3. Check wiring harness

Fault effect and breakdown warning


Driver information
Warning light:
MIL on (in 2nd driving cycle);

Service instruction
none