The engine oil pressure (EOP) sensor changes resistance based on engine oil pressure. The powertrain control module (PCM) monitors the signal circuit of the EOP sensor. When the engine oil pressure is high, the sensor resistance is high and the PCM senses a high signal voltage. When the engine oil pressure is low, the sensor resistance is low and the PCM senses a low signal voltage. The PCM sends the engine oil pressure information to the instrument panel cluster (IPC) via the class 2 serial data circuit.
This diagnostic procedure supports the following DTC:
DTC P0523 Engine Oil Pressure (EOP) Sensor Circuit High Voltage
• | The engine is running. |
• | DTC P1635 for the 4.3L engine or DTC P0641 for the 4.8L, 5.3L, 6.0L and 6.6L engine is not present. |
• | The PCM detects that the EOP sensor signal circuit is greater than 4.6 volts. |
• | The above condition is present for greater than 9 seconds. |
The PCM records the operating conditions at the time that the diagnostic test fails. The PCM displays this information in the Failure Records on the scan tool.
• | The DTC becomes history when the conditions for setting the DTC are no longer present. |
• | The history DTC is cleared after 40 malfunction-free warm-up cycles. |
• | The PCM receives the clear code command from the scan tool. |
• | 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 in determining how many miles since the DTC set. The Fail Counter and the Pass Counter can help determine how many ignition cycles that the diagnostic test reported a pass and/or a fail. |
The number below refers to the step number on the diagnostic table.
Step | Action | Values | Yes | No | ||||||
---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Instrument Cluster Schematics Connector End View References: Master Electrical Component List | ||||||||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |||||||
2 |
Does the Engine Oil Pressure Sensor parameter display greater than the specified value? | 0 kPa (0 psi) - 6.6L diesel only 4.6 V | Go to Step 3 | Go to Diagnostic Aids | ||||||
Does the Engine Oil Pressure Sensor parameter display less than the specified value? | 550 kPa (80 psi) - 6.6L diesel only 0.4 V | Go to Step 4 | Go to Step 5 | |||||||
4 |
Is the resistance less than the specified value? | 5 ohms | Go to Step 7 | Go to Step 6 | ||||||
5 | Test the EOP sensor signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 11 | Go to Step 8 | ||||||
6 | Test the low reference circuit of the EOP sensor for an open or for a high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 11 | Go to Step 8 | ||||||
7 | Inspect for poor connections at the harness connector of the EOP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 11 | Go to Step 9 | ||||||
8 | Inspect for poor connections at the harness connector of the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 11 | Go to Step 10 | ||||||
9 | Replace the EOP sensor. Refer to the following procedures:
Did you complete the replacement? | -- | Go to Step 11 | -- | ||||||
10 | Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 11 | -- | ||||||
11 |
Does the DTC reset? | -- | Go to Step 2 | System OK |