2012 Jeep Wrangler JK Factory Service Manual 28 - DTC-Based Diagnostics

P0135-O2 SENSOR 1/1 HEATER PERFORMANCE

P0135-O2 SENSOR 1/1 HEATER PERFORMANCE

For a complete wiring diagram, refer to the Wiring Information.



Possible Causes

(K891) O2 SENSOR 1/1 HEATER CONTROL CIRCUIT SHORTED TO VOLTAGE
(K891) O2 SENSOR 1/1 HEATER CONTROL CIRCUIT SHORTED TO GROUND
(K891) O2 SENSOR 1/1 HEATER CONTROL CIRCUIT OPEN/HIGH RESISTANCE
(F344) FUSED ASD RELAY OUTPUT CIRCUIT OPEN/HIGH RESISTANCE
OXYGEN SENSOR
POWERTRAIN CONTROL MODULE (PCM)

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).


1. DTC IS ACTIVE

1. Ignition on, engine not running.
2. With the scan tool, Clear DTCs in the PCM.
3. Start the engine and allow the engine to reach normal operating temperature.
4. Monitor the scan tool for at least two minutes.
5. With the scan tool, select View DTCs.


Is the status Active for this DTC?

Yes


No


2. CHECK THE (K891) O2 SENSOR 1/1 HEATER CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
1. Turn the ignition off.
2. Disconnect the Oxygen Sensor harness connector.
3. Disconnect the PCM C1 harness connector.
4. Remove the ASD Relay from the TIPM.
5. Connect a jumper wire between cavity 30 and cavity 87 of the ASD Relay Connector.
6. Turn the ignition on.
7. Measure the voltage of the (K891) O2 Sensor 1/1 Heater Control circuit at the Oxygen Sensor harness connector.


Is there any voltage present?

Yes


No


3. CHECK THE (F344) FUSED ASD RELAY OUTPUT VOLTAGE
1. Remove the jumper wire and re-install the ASD Relay.
2. Measure the voltage of the (F344) Fused ASD Relay Output circuit at the Oxygen Sensor harness connector.


Is the voltage reading equal to battery voltage?

Yes


No


4. CHECK THE (K891) O2 SENSOR 1/1 HEATER CONTROL CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Measure the resistance between ground and the (K891) O2 Sensor 1/1 Heater Control circuit at the Oxygen Sensor harness connector.


Is the resistance above 10k Ohms?

Yes


No


5. CHECK THE (K891) O2 SENSOR 1/1 HEATER CONTROL CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Measure the resistance of the (K891) O2 Sensor 1/1 Heater Control circuit between the Oxygen Sensor harness connector and the PCM C1 harness connector.


Is the resistance below 5.0 Ohms?

Yes


No


6. OXYGEN SENSOR

1. Reconnect the PCM C1 harness connector.
2. Replace the Oxygen Sensor in accordance with the service information.
3. Start the engine.
4. Allow the engine to reach normal operating temperature.
5. Monitor the scan tool for at least two minutes.
6. With the scan tool, select View DTCs.


Is the status Active for this DTC?

Yes


No


7. POWERTRAIN CONTROL MODULE

1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Oxygen Sensor and the Powertrain Control Module.
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals.
4. Perform any Technical Service Bulletins that may apply.


Were any problems found?

Yes


No