P0139

Test 1:

Test 2 - 7:

SYMPTOM
P0139-1/1 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. Ambient Temp great than 6.6° C (44° F), Baro greater than 22.13 Hg, Battery voltage 10.5 volts, MAP greater than 11.9 and less than 18.15 inches Hg, RPM greater than 1216 and less than 1984 and VSS greater 19 and less than 46 MPH.

SET CONDITION
The oxygen sensor signal voltage is has not switched below 0.33 volts to above 0.61 volts in 411 seconds of engine run. Two trip fault.

POSSIBLE CAUSES
- Good trip equal to zero
- ASD Relay
- (A142) ASD relay output circuit open
- Fused B+ circuit open
- (A142) ASD output circuit open
- PCM