DTC P0520. Chevrolet Uplander

For 1990-2009 cars only

Makes 🢒 Chevrolet 🢒 2005 🢒 Uplander - 4WD 🢒 Body 🢒 Instrument Panel, Gages, and Console 🢒 DTC P0520

DTC Descriptor

DTC P0520 : Engine Oil Pressure (EOP) Sensor Circuit

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 Switch Signal	1	P0520	P0520	--
1. Engine Oil Pressure Indicator Malfunction

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 powertrain control module (PCM) should detect a low signal voltage input. With the engine running, the pressure switch opens, and the PCM should detect a high signal voltage input. The PCM tests the state of the EOP circuit with the ignition switch turned ON, and the engine turned OFF. When the oil pressure is low, the PCM sends a serial data message to the body IPC requesting the EOP indicator turned ON.

Conditions for Running the DTC

The ignition is ON, with the engine ON.

Conditions for Setting the DTC

•	The PCM detects that the EOP sensor signal circuit is open.

•	The above condition is present for greater than 5 seconds.

Action Taken When the DTC Sets

•	The PCM records the operating conditions at the time the diagnostic test fails. The PCM displays this information in the Failure Records on the scan tool.

•	The instrument panel cluster (IPC) illuminates the EOP 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.

Diagnostic Aids

Using the Failure Records data may help locate an intermittent condition. If you cannot duplicate the DTC, the information in the Failure Records can help determine how many miles since the DTC set. The Fail Counter and Pass Counter can help determine how many ignition cycles that the diagnostic test reported a pass and/or a fail.

Reference Information

Schematic Reference

•	Instrument Cluster Schematics

•	Engine Controls Schematics

Connector End View Reference

•	Instrument Panel, Gages, and Console Connector End Views

•	Engine Controls Connector End Views

Electrical Information Reference

•	Circuit Testing

•	Connector Repairs

•	Testing for Intermittent Conditions and Poor Connections

•	Wiring Repairs

Scan Tool Reference

Scan Tool Data List

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 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 PCM.

Ignition ON, install a 3-Amp 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 PCM.

If all circuits test normal, replace the engine oil pressure switch.

Repair Instructions

Important: Always perform the Diagnostic Repair Verification after completing the diagnostic procedure.

•	Engine Oil Pressure Sensor and/or Switch Replacement

•	Control Module References for the ECM replacement, setup, and programming