P0137

Test 1 - 4:

Test 5 - 8:

SYMPTOM
P0137-O2 SENSOR 1/2 VOLTAGE LOW

TEST NOTE
This symptom is diagnosed using the P0131-O2 SENSOR 1/1 VOLTAGE LOW.

WHEN MONITORED
Engine Running for less than 30 seconds. O2 Sensor Heater Temperature less than 376 °C (708 °F) Battery voltage greater than 10.99 volts.

SET CONDITION
The oxygen sensor signal voltage is below 2.5196 volts for 3 seconds. One trip Fault.

POSSIBLE CAUSES
- O2 Sensor Below 2.52 Volts
- O2 Sensor
- O2 Return Circuit Shorted To Ground
- O2 Signal Circuit Shorted To Ground
- O2 Signal Circuit Shorted To O2 Return Circuit
- O2 Signal Shorted To Heater Ground Circuit
- PCM Return Circuit
- PCM Signal Circuit