Circuit Description
When the oil pressure is above 4.5 psi, the engine oil pressure switch opens, and the powertrain control module (PCM) senses a high signal voltage. The PCM monitors the oil pressure switch signal circuit and sends a class 2 message to the instrument panel cluster (IPC) indicating the switch status. When the engine oil pressure is low, the engine oil pressure switch closes, and the signal circuit is low.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0520 Engine Oil Pressure (EOP) Sensor Circuit
Conditions for Running the DTC
| • | The ignition is ON with the engine ON. |
| • | 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 in the diagnostic table.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Instrument Cluster Schematics and Engine Controls Schematics in Engine Controls - 3.8L Connector End View: Powertrain Control Module Connector End Views in Engine Controls - 3.8L | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
2 |
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 |
Does the Engine Oil Pressure Switch parameter display Low? | Go to Step 6 | Go to Step 4 | |
4 | Test the signal circuit of the engine oil pressure 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 engine oil pressure 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 engine oil pressure 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 engine oil pressure switch. Refer to 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 |
Does the DTC reset? | Go to Step 2 | System OK |
