Diagnostic Fault Information
Important: Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
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)/powertrain control module should detect a low signal voltage input. With the engine running, the pressure switch opens, and the ECM/PCM should detect a high signal voltage input. The ECM/PCM tests the state of the EOP circuit with the ignition switch turned ON, and the engine turned OFF. If the ECM/PCM detects a high voltage input on the EOP signal circuit, DTC P0520 sets. When the oil pressure is low, the ECM/PCM sends a GMLAN serial data message to the body control module (BCM) requesting the EOP indicator turned ON. The IPC illuminates the EOP indicator when the instrument panel cluster (IPC) receives a serial data message from the BCM requesting the EOP indicator turned ON.
Reference Information
Schematic Reference
| • | Engine Controls Schematics for the 2.0L engine |
| • | Engine Controls Schematics for the 2.2L engine |
| • | Engine Controls Schematics for the 2.4L engine |
Connector End View Reference
| • | Powertrain Control Module Connector End Views for the 2.0L engine |
| • | Engine Control Module Connector End Views for the 2.2L engine |
| • | Engine Control Module Connector End Views for the 2.4L 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 after completing the diagnostic procedure.
- Engine Oil Pressure Sensor and/or Switch Replacement for the 2.0L engine
- Engine Oil Pressure Sensor and/or Switch Replacement for the 2.2L engine
- Engine Oil Pressure Sensor and/or Switch Replacement for the 2.4L engine
- Control Module References for the ECM/PCM replacement, setup, and programming
