Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptor
DTC P0520: Engine Oil Pressure (EOP) Switch CircuitDiagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Oil Pressure Switch Signal | 1 | P0520 | 1 | -- |
Low Reference | -- | P0520 | -- | -- |
1. Engine Oil Pressure Indicator Malfunction | ||||
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 engine is running.
Conditions for Setting the DTC
| • | The ECM detects that the EOP sensor signal circuit is pulled low. |
| • | 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 instrument panel cluster (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
Connector End View Reference
Description and Operation
Instrument Cluster Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for 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. |
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the engine oil pressure (EOP) switch.
- Ignition OFF, test for less than 1 ohm between the low reference circuit terminal A and ground.
- Ignition ON, verify the scan tool Engine Oil Pressure Switch parameter is OK.
- Ignition ON, install a 3A fused jumper wire between the signal circuit terminal B and the ground circuit terminal A. Verify the scan tool Engine Oil Pressure Switch parameter is Low.
- If all circuits test normal, test or replace the engine oil pressure switch.
| ⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM. |
| ⇒ | If not the specified value, test the signal circuit for a short to ground. If the circuit tests normal, replace the ECM. |
| ⇒ | If not the specified value, test the signal circuit for an open/high resistance. If circuit test normal, replace the ECM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for ECM replacement, setup, and programming |
