P0523
DTC P0523 Engine Oil Pressure (EOP) Sensor Circuit High Voltage
Refer to Engine Control Schematics Automatic Engine Shutdown and Warning .
Circuit Description
The engine oil pressure (EOP) sensor is mounted in the top rear of the engine. The EOP sensor measures changes in engine oil pressure. The EOP sensor has a 5 volt reference, a ground and a signal circuit.
The EOP sensor changes resistance based on pressure. When the PCM senses a signal voltage is higher than the normal operating range of the sensor, this DTC sets.
Conditions for Running the DTC
The engine is running
Conditions for Setting the DTC
The engine oil pressure sensor is more than 4.5 volts.
Action Taken When the DTC Sets
* The PCM stores the DTC information into memory when the diagnostic runs and fails
* The malfunction indicator lamp (MIL) will not illuminate
* The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Failure Records
Conditions for Clearing the MIL/DTC
* A History DTC will clear after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
* A last test failed (Current DTC) will clear when the diagnostic runs and does not fail.
* Use a scan tool in order to clear the MIL/DTC.
Diagnostic Aids
Important: Remove any debris from the PCM/TAC module connector surfaces before servicing the PCM\TAC module. Inspect the PCM/TAC module connector gaskets when diagnosing/replacing the modules. Ensure that the gaskets are installed correctly. The gaskets prevent water intrusion into the PCM/TAC modules.
* Inspect the PCM/TAC module connector gaskets. Refer to Powertrain Control Module Controlled Tachometer Diagnosis Powertrain Control Module Controlled Tachometer Diagnosis.
* Inspect for the following conditions that may cause an intermittent:
- Misrouted harness
- Rubbed through wire insulation
- Broken wire inside the insulation
* The PCM 5 volt reference circuits are internally connected within the PCM. If all the engine oil pressure sensor circuits check to be OK, inspect related 5 volt reference circuits.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
2. This step determines if the malfunction is present. For any test that requires probing of the PCM or any component harness connectors, use the connector test adapter kit. Using this kit prevents damage to the harness connector terminals.
3. Using the Freeze Frame and Failure Records data may aid in locating an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame and Failure Records data can help determine how many miles since the DTC set. The Fail Counter and Pass Counter can also help determine how many ignition cycles the diagnostic reported a pass and a fail. Operate vehicle within the same Freeze Frame conditions (RPM, load, vehicle speed, temperature etc.) that you observed. This will isolate when the DTC failed.
4. This step checks if the signal circuit is shorted to a voltage.
5. This step checks if a ground circuit is available at the engine oil pressure sensor.
