Diagnostic Fault Information
Important: Always perform the Diagnostic System Check - Vehicle .
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Engine Oil Pressure Sensor Signal Circuit | 1 | P0520 | P0520 | -- |
Engine Oil Pressure Sensor Ground Circuit | -- | P0520 | -- | -- |
1. Engine Oil Pressure Indicator Always On | ||||
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. The ECM tests the state of the EOP signal circuit with the ignition switch turned ON, and the engine turned OFF. The instrument panel cluster (IPC) illuminates the EOP indicator when the IPC receives a serial data message from the ECM requesting the EOP indicator turned ON.
Reference Information
Schematic Reference
Connector End View Reference
| • | Engine Controls Connector End Views for the 4.6L engine |
| • | Powertrain Control Module Connector End Views for the 3.8L engine |
Electrical Information Reference
Scan Tool Reference
Circuit/System Testing
Important: Do not turn the key to the crank position or engage the starter at any time during diagnosis.
- Ignition ON, verify the scan tool Engine Oil Pressure (EOP) Switch parameter is Low.
- Ignition OFF, disconnect the EOP switch.
- Ignition ON, verify the scan tool Engine Oil Pressure Switch parameter is OK.
| ⇒ | If not Low, replace the instrument panel cluster (IPC). |
| ⇒ | If not OK, test the signal circuit of the EOP switch for a short to ground. If the circuit tests normal, replace the ECM. |
| ⇒ | If OK, replace the EOP switch. |
Repair Instructions
Important: Always perform the Diagnostic Repair Verification .
| • | Engine Oil Pressure Sensor and/or Switch Replacement for the 4.6L engine |
| • | Engine Oil Pressure Sensor and/or Switch Replacement for the 3.8L engine |
| • | Control Module References for IPC replacement, setup and programming |
