P0520
DTC P0520
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructionsprovide an overview of each diagnostic category.
DTC Descriptor
DTC P0520
- Engine Oil Pressure (EOP) Sensor Circuit
Diagnostic Fault Information
Circuit/System Description
The engine oil pressure (EOP) switch is a normally closed switch that opens with the proper oil pressure. With the ignition switch turned ON and the engine not running, the engine control module (ECM) should detect a low signal voltage input. With the engine running, the pressure switch opens, and the ECM should detect a high signal voltage input. When the oil pressure is low, the ECM sends a serial data message to the body control module (BCM) requesting the EOP indicator turned ON. The instrument panel cluster (IPC) illuminates the EOP indicator when the IPC receives a serial data message from the BCM requesting the EOP indicator turned ON.
Conditions for Running the DTC
The ignition is ON, with the engine OFF.
Conditions for Setting the DTC
* The ECM detects that the EOP sensor signal circuit is pulled high.
* The above condition is present for greater than 10 seconds.
Action Taken When the DTC Sets
* The ECM records the operating conditions at the time the diagnostic test fails. The ECM displays this information in the Failure Records on the scan tool.
* The IPC illuminates the engine oil pressure indicator.
Conditions for Clearing the DTC
* The DTC becomes history when the conditions for setting the DTC are no longer present.
* The history DTC clears after 40 malfunction-free warm-up cycles.
Reference Information
Schematic Reference
Instrument Cluster Schematics Instrument Cluster Schematics
Connector End View Reference
Component Connector End Views Connector End Views By Name
Description and Operation
* Instrument Cluster Description and Operation Description and Operation
* Indicator/Warning Message Description and Operation (Radio) Indicator/Warning Message (Radio)
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
Scan Tool Reference
Control Module References Programming and Relearningfor scan tool information
Circuit/System Verification
Ignition ON, engine running, verify the scan tool Engine Oil Pressure Switch parameter is OK.
If not the specified value, refer to:
* Oil Pressure Diagnosis and Testing Oil Pressure Diagnosis and Testingfor the 3.6L engine
* Oil Pressure Diagnosis and Testing Oil Pressure Diagnosis and Testingfor the 2.4L engine
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the engine oil pressure (EOP) switch.
2. Ignition OFF, test for less than 1 ohm between the low reference circuit terminal B and ground (LY7 only).
• If greater than the specified value, test the circuit for an open/high resistance.
3. Ignition ON, verify the scan tool Engine Oil Pressure Switch parameter is OK.
• If not the specified value, test the signal circuit terminal A for a short to ground. If the circuit tests normal, replace the ECM.
4. Ignition ON, install a 3-A fused jumper wire between the signal circuit terminal A and ground. Verify the scan tool Engine Oil Pressure Switch parameter is Low.
• If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.
5. If all circuits test normal, test or replace the engine oil pressure switch.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Engine Oil Pressure Switch Replacement Service and Repairfor the 2.2L or 2.4L engine
* Engine Oil Pressure Sensor and/or Switch Replacement Service and Repairfor the 3.6L engine
* Control Module References Programming and Relearningfor the ECM replacement, setup, and programming