Fault description

Diagnosis monitors the upper and lower voltage limit of the oxygen sensor 2 after catalytic converter during the active test. The active test is started when a fault was found by trim controller diagnosis.

The fault is detected when the voltage of the oxygen sensor 2 after catalytic converter is greater than 0.669 V (too rich).

Possible fault cause:

• Oxygen sensor 2 after catalytic converter defective
• Leak in silencer system upstream of oxygen sensor 2 after catalytic converter
• Wiring harness of oxygen sensor 2 after catalytic converter defective