P0139

Test 1:

Tests 2 - 5:

Test 6:

SYMPTOM
P0139-1/2 O2 SENSOR SLOW RESPONSE

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

WHEN MONITORED
Start engine. Allow engine to idle. For 1st part of test, if limits are exceeded, test passes. If not, 2nd part of test runs. Engine running for grater than 295 seconds. AMB/BATT TEMP > 44 °F, Baro > 22.13" HG, MAP > 13.8 & < 21.6" HG, RPM > 1400 & < 2500 (4cylinder) RPM > 1120 & <1950 (6 cylinder) and VSS > 22 AND < 60 MPH.

SET CONDITION
The oxygen sensor signal voltage is has not switched below 0.35 volts to above 0.53 volts in 411 seconds of engine run. Two trip fault.

POSSIBLE CAUSES
- Intermittent condition
- Exhaust leak
- O2 sensor signal circuit voltage drop
- O2 sensor ground circuit voltage drop
- O2 sensor