GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2005 🢒 Impala 🢒 Body 🢒 Instrument Panel, Gages, and Console 🢒 DTC P0520

Circuit Description

With low oil pressure, the engine oil pressure (EOP) switch closes, and the signal circuit is low. With oil pressure above 4.5 psi, the EOP switch opens, and the signal circuit is high. The powertrain control module (PCM) monitors the oil pressure switch signal circuit and sends a class 2 message to the instrument panel cluster (IPC) indicating the switch status.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0520 Engine Oil Pressure (EOP) Sensor Circuit

Conditions for Running the DTC
    • DTCs P0117, P0118, and P1114 are not set.
    • The ignition is ON, with the engine OFF.
    • Engine temperature is 10°C (50°F) less than the last key off temperature.

Conditions for Setting the DTC
    • The PCM detects that the oil pressure switch signal circuit is high with the ignition ON and the engine OFF.
    • The above condition is present for greater than 10 seconds.

Action Taken When the DTC Sets

The PCM stores the conditions that are present when the DTC sets as Failure Records data only. This information is not stored as Freeze Frame data.

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.
    • The PCM receives the clear code command from the scan tool.

Test Description

The number below refers to the step number on the diagnostic table.

  1. This step tests for the proper operation of the circuit in the low voltage range. If the fuse in the jumper opens when you perform this test, the signal circuit is shorted to voltage.

Step

Action

Yes

No

Schematic Reference: Instrument Cluster Schematics

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2
  1. Connect a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, observe the Engine Oil Pressure Switch parameter in the powertrain control module (PCM) Engine Data 2 data list.

Does the Engine Oil Pressure Switch parameter display Low?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

  1. Turn OFF the ignition.
  2. Disconnect the engine oil pressure (EOP) switch connector.
  3. Connect a 3-amp fused jumper wire between the signal circuit of the oil pressure switch connector and a good ground.
  4. Turn ON the ignition.
  5. With a scan tool, observe the Engine Oil Pressure Switch parameter in the PCM Engine Data 2 data list.

Does the Engine Oil Pressure Switch parameter display Low?

Go to Step 6

Go to Step 4

4

Test the signal circuit of the EOP switch for an open, high resistance, or a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 5

5

Test the ground circuit of the EOP switch for an open or a high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 7

6

Inspect for poor connections at the harness connector of the EOP switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 8

7

Inspect for poor connections at the harness connector of the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 9

8

Replace the EOP switch. Refer to Engine Oil Pressure Sensor and/or Switch Replacement in Engine Mechanical - 3.4L or Engine Oil Pressure Sensor and/or Switch Replacement in Engine Mechanical - 3.8L.

Did you complete the replacement?

Go to Step 10

--

9

Replace the PCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 10

--

10
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK