P0137

Tests 1 - 3:

Tests 4 - 5:

SYMPTOM
P0137 - 1/2 O2 SENSOR VOLTS SHORTED TO GROUND

WHEN MONITORED
With engine coolant temperature above 170 °F on the previous key ON, after a cold start, engine coolant temperature below 98 °F, and ambient/battery temperature sensor reading within 27 °F of engine coolant temperature.

SET CONDITION
The oxygen sensor signal voltage is below 0.156 volt for 28 seconds after starting engine.

POSSIBLE CAUSES
- 1/2 O2 sensor defective
- 1/2 O2 sensor signal circuit shorted to ground
- 1/2 O2 sensor signal circuit shorted to ground circuit
- PCM defective