P0139

Test 1 - 5:

SYMPTOM
P0139-O2 SENSOR 1/1 SLOW RESPONSE

TEST NOTE
This symptom is diagnosed using the test P0133-O2 SENSOR 1/1 SLOW RESPONSE.

WHEN MONITORED
Start and drive vehicle greater than 20 MPHand less than 55 MPH.Throttle open for a minimum 120 seconds. Coolant Temp greater than 70°C (158°F) Catalytic Converter Temperature greater than 600°C (1112°F)

SET CONDITION
The O2 sensor voltage switches properly from lean to rich during monitoring. Two Trip Fault.


POSSIBLE CAUSES
- Good trip equal to zero
- Exhaust leak
- O2 signal circuit
- O2 return circuit
- O2 sensor