Chrysler Pacifica CS 2004, Service Manual, Page: 95 / 370

Symptom List:
P0131-O2 SENSOR 1/1 VOLTAGE LOW
P0137-O2 SENSOR 1/2 VOLTAGE LOW
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be P0131-O2 SENSOR 1/1 VOLTAGE
LOW.
When Monitored and Set Condition:
P0131-O2 SENSOR 1/1 VOLTAGE LOW
When Monitored: Engine Running.
Set Condition: The oxygen sensor signal voltage is below 2.402 volts for 9 seconds. Two
trip Fault.
P0137-O2 SENSOR 1/2 VOLTAGE LOW
When Monitored: Engine Running.
Set Condition: The oxygen sensor signal voltage is below 2.402 volts for 9 seconds. Two
trip Fault.
POSSIBLE CAUSES
O2 SENSOR BELOW 1.5 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
89
DRIVEABILITY - NGC