P0052

P0052-O2 SENSOR 2/1 HEATER CIRCUIT HIGH





For a complete wiring diagram refer to Diagrams/Electrical.


- When Monitored:

Continuously during O2 heater operation with battery voltage between 10.4 and 15.75 volts.

- Set Condition:

The PCM detects that the O2 sensor heater element input is above the maximum acceptable voltage. One trip fault. Three good trips to turn off the MIL.







Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.


Diagnostic Test


1. ACTIVE DTC

Start the engine and allow it to idle for at least 60 seconds.


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 can result in personal injury or death.

With a scan tool, select View DTCs.

Is the DTC Active at this time?

Yes

- Go To 2

No

- Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition


2. O2 HEATER ELEMENT

Turn the ignition off.


NOTE: Allow the O2 Sensor to cool down to room temperature.

Disconnect the 2/1 O2 Sensor harness connector.

Measure the resistance across the O2 Sensor Heater element, between the O2 Heater Control terminal and the Heater ground terminal at the component connector.


NOTE: O2 Heater Element resistance values should be measured at 21.1° C (70° F). The resistance value will vary with different temperature values.

Is the O2 Sensor Heater Element resistance between 2.0 and 30.0 ohms?

Yes

- Go To 3

No

- Replace the O2 Sensor.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test


3. (K199) O2 2/1 HEATER CONTROL CIRCUIT





Ignition on, engine not running.

Using a 12-volt test light connected to ground, probe the (K199) O2 2/1 Heater Control circuit in the O2 Sensor harness connector.


NOTE: Make sure the test light is probing the circuit before actuating the Heater Test or a DTC may set and not allow the actuation.

With the scan tool, actuate the O2 Heater Test with the Sensor harness connector still disconnected.

Does the test light illuminate brightly and flash on and off during the actuation?

Yes

- Go To 4

No

- Go To 5


4. (Z906) O2 2/1 HEATER GROUND CIRCUIT OPEN





Turn the ignition off.

Measure the resistance between an engine ground and the (Z906) O2 2/1 Heater ground circuit in the O2 Sensor harness connector.

Is the resistance below 5.0 ohms?

Yes

- Replace the O2 Sensor.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Repair the open in the (Z906) O2 2/1 Heater ground circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test


5. (K199) O2 2/1 HEATER CONTROL CIRCUIT SHORTED TO VOLTAGE





Turn the ignition off.

Disconnect the C2 PCM harness connector.

Ignition on, engine not running.

Measure the voltage on the (K199) O2 2/1 Heater Control circuit at the 2/1 O2 Sensor harness connector.

Is there any voltage present?

Yes

- Repair the short to voltage in the (K199) O2 2/1 Heater Control circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go To 6


6. (K199) O2 2/1 HEATER CONTROL CIRCUIT OPEN





Turn the ignition off.


CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.

Measure the resistance of the (K199) O2 2/1 Heater Control circuit from the O2 Sensor harness connector to the appropriate terminal of special tool #8815.

Is the resistance below 5.0 ohms?

Yes

- Go To 7

No

- Repair the open in the (K199) O2 2/1 Heater Control circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test


7. PCM

NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.

Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.

Were there any problems found?

Yes

- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Replace and program the Powertrain Control Module.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test