P0523

P0523-ENGINE OIL PRESSURE SENSOR CIRCUIT HIGH





For a complete wiring diagram Consult Diagrams/Electrical.

- When Monitored:
With the ignition on. Battery voltage greater than 10 volts.

- Set Condition:
The Engine Oil pressure signal is greater than the calibrated amount. One Trip Fault.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Initial Inspection and Diagnostic Overview.

Diagnostic Test

1. ACTIVE DTC
NOTE: Make sure that the engine oil is at the proper level. Also, check the customers oil change history to ensure that the oil is being changed at the correct intervals and that the proper oil viscosity is being used.

Start the engine and allow it to reach normal operating temperature.

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 the 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. ENGINE OIL PRESSURE SENSOR




Turn the ignition off.
Disconnect the Engine Oil Pressure Sensor harness connector.
Ignition on, engine not running.
With a scan tool, monitor the Engine Oil Pressure Sensor voltage.
Connect a jumper wire between the (G6) Engine Oil Pressure Signal circuit and the (K900) Sensor Ground circuit in the Engine Oil Pressure Sensor harness connector.
Is the voltage below 0.5 of a volt with the jumper wire installed?

Yes

- Verify that there is good pin to terminal contact in the Sensor and Powertrain Control Module connectors. Replace the Engine Oil Pressure Sensor if no problems were found in the connectors.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 3

NOTE: Remove the jumper wire before continuing.


3. (G6) ENGINE OIL PRESSURE SIGNAL CIRCUIT SHORTED TO VOLTAGE




Turn the ignition off.
Disconnect the C1 and C2 PCM harness connectors.
Ignition on, engine not running.
Measure the voltage on the (G6) Engine Oil Pressure Signal circuit in the Engine Oil Pressure Sensor harness connector.
Is there any voltage present?

Yes

- Repair the short to voltage in the (G6) Engine Oil Pressure Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 4

4. (G6) ENGINE OIL PRESSURE SIGNAL 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 (G6) Engine Oil Pressure Signal circuit from the Engine Oil Pressure Sensor harness connector to the appropriate terminal of special tool #8815.
Is the resistance below 5.0 ohms?

Yes

- Go To 5

No

- Repair the open in the (G6) Engine Oil Pressure Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

5. (G6) ENGINE OIL PRESSURE SIGNAL CIRCUIT SHORTED TO THE (F855) 5-VOLT SUPPLY CIRCUIT




Measure the resistance between the (G6) Engine Oil Pressure Signal circuit and the (F855) 5-volt Supply circuit in the Engine Oil Pressure Sensor harness connector.
Is the resistance below 100 ohms?

Yes

- Repair the short between the (F855) 5-volt Supply circuit and the (G6) Engine Oil Pressure Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 6

6. (K900) SENSOR GROUND CIRCUIT OPEN




Measure the resistance of the (K900) Sensor Ground circuit from the Engine Oil Pressure 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 (K900) Sensor Ground circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

7. POWERTRAIN CONTROL MODULE (PCM)
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Engine Oil Pressure Sensor and the Powertrain Control Module (PCM).
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Sensor and Powertrain Control Module connectors.
Search for any Technical Service Bulletins that may apply.
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.