For a complete wiring diagram, refer to the Wiring
Information.
When Monitored:
Continuously
after 15 seconds of engine runtime, no O2 Sensor Heater DTCs present
and battery voltage greater than 10.4 volts.
Set Condition:
The Oxygen
Sensor reference voltage is below 0.9 volts for 60 seconds. The DTC
will set as Pending after one trip and Active after two trips. Three
good trips to turn off the MIL.
The most likely cause
of this DTC is (K902) O2 Sensor Return circuit shorted to ground.
1.
Ignition on, engine
not running.
2.
With the scan tool,
select View DTCs. Copy DTC and Freeze Frame information.
3.
Start the engine.
WARNING:
When the engine is operating, do
not stand in direct line with the fan. Do not put your hands near
the pulleys, belts or fan. Do not wear loose clothing. Failure to
follow these instructions may result in possible serious or fatal
injury.
4.
Allow the engine
to reach normal operating temperature.
With the scan tool,
monitor the O2 Sensor 1/1 and 2/1 voltage readings.
5.
Connect a jumper
between the (K41) O2 Sensor 1/1 Signal circuit and the (K902) O2 Sensor
Return circuit in the O2 Sensor 1/1 harness connector.
6.
Connect a jumper
between the (K43) O2 Sensor 2/1 Signal circuit and the (K902) O2 Sensor
Return circuit in the O2 Sensor 2/1 harness connector.
Is the
voltage between 2.3 and 2.7 volts with the jumper installed?
Yes
Verify that there is
good pin to terminal contact in the O2 Sensors and Powertrain Control
Module connectors. Replace the O2 Sensor not indicating the specified
voltage if no problems were found with the connections. (Refer to 14 - Fuel System/Fuel Injection/SENSOR,
Oxygen - Removal)
.
Using the wiring
diagram/schematic as a guide, inspect the wiring and connectors between
the Oxygen Sensors and the Powertrain Control Module (PCM).
2.
Look for any chafed,
pierced, pinched or partially broken wires.
3.
Look for broken,
bent, pushed out or corroded terminals. Verify that there is good
pin to terminal contact in the Oxygen Sensors and Control Module connectors.
4.
Perform any Technical
Service Bulletins that may apply.
