FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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P0138

Tests 183 - 187:




Test 188:




SYMPTOM
P-0138 O2 SENSOR 1/2 SHORT TO VOLTAGE

WHEN MONITORED
With the ignition key on.

SET CONDITION
The engine running for more than 2 minutes and coolant temperature above 176 degrees F. The oxygen sensor signal voltage is above 1.2 volts for 30 seconds.

POSSIBLE CAUSES
- O2 sensor 1/2 signal circuit shorted to voltage
- O2 sensor 1/2 connector & harness intermittent def
- O2 sensor 1/2 connector and harness observable def
- O2 sensor 1/2 defective
- PCM connector observable defect