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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1999 🢒 Corvette 🢒 Engine 🢒 Engine Controls - 5.7L 🢒 Engine Oil Pressure Sensor and/or Switch Diagnosis

Object Number: 383968 Size: SF
Engine Controls Component Views
Cell 20: Miscellaneous
OBD II Symbol Description Notice
Handling ESD Sensitive Parts Notice

Circuit Description

The Engine Oil Pressure sensor is mounted at the top rear of the engine. The Engine Oil Pressure sensor measures changes in engine oil pressure. The Engine Oil Pressure sensor has a 5 volt reference, a ground and a signal circuit.

The Engine Oil Pressure sensor changes resistance based on changes in engine oil pressure. The PCM sends the engine oil pressure sensor information to the Instrument Panel Cluster (IPC) via the class 2 circuit. Whe nthe engine oil pressure is out of range the Driver Information Center displays a message.

Diagnostic Aids:

Important: 

   • Remove any debris from the PCM\TAC module connector surfaces before servicing the PCM\TAC module. Inspect the PCM\TAC module connector gaskets when diagnosing/replacing the modules. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion into the PCM\TAC modules.
   • For any test that requires probing the PCM or a component harness connector, use the Connector Test Adapter Kit J 35616 . Using this kit prevents damage to the harness/component terminals. Refer to Using Connector Test Adapters in Wiring Systems.

    • The following may cause an intermittent:
       - Poor connections; Refer to Intermittents and Poor Connections Diagnosis in Wiring Systems.
       - Mis-routed harness.
       - Rubbed through wire insulation.
       - Broken wire inside the insulation.
    • Inspect the ground circuit for an open if the EOP gauge displays the maximum pressure.
    • For an intermittent, refer to Symptoms .

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step determines if the malfunction is present.

  2. This step tests if the ground circuit is open.

    3.

  3. This step tests if the signal circuit is shorted to a voltage.

    4.

  4. This step verifies if a ground circuit is available at the Engine Oil Pressure sensor.

Step

Action

Value(s)

Yes

No

1

Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

Important:: 

   • This table assumes there are no engine oil pressure sensor DTCs. This table only diagnoses a high voltage/pressure condition.
   • Before proceeding with the Engine Oil Pressure sensor diagnostic, perform the engine oil pressure test. Refer to Oil Pressure Diagnosis and Testing in Engine Mechanical-5.7L.

  1. Turn ON the ignition leaving the engine OFF.
  2. Monitor the Engine Oil Pressure voltage using the scan tool.

Is the Engine Oil Pressure sensor voltage above the specified value?

4.0V

Go to Step 3

Go to Diagnostic Aids

3

  1. Remove the intake manifold. Refer to Intake Manifold Replacement in Engine Mechanical-5.7L.
  2. Disconnect the Engine Oil Pressure sensor electrical connector.
  3. Observe the Engine Oil Pressure sensor voltage displayed on the scan tool.

Is the Engine Oil Pressure sensor voltage below the specified value?

1V

Go to Step 4

Go to Step 6

4

Probe the sensor ground circuit with the test lamp J 35616-200 connected to B+.

Is the test lamp illuminated?

--

Go to Step 5

Go to Step 7

5

Measure the voltage at the 5 volt reference circuit to ground using the DMM J 39200 .

Is the voltage greater than the specified value?

5V

Go to Step 9

Go to Step 11

6

  1. Test the Engine Oil Pressure signal circuit for a short to voltage or a short to the 5 volt reference circuit.
  2. Repair the Engine Oil Pressure sensor signal circuit if it is shorted. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

System OK

Go to Step 10

7
  1. Disconnect the PCM connector C1 located on the same side as the manufacturer's logo. Refer to Powertrain Control Module/Throttle Actuator Control Module Replacement .
  2. Inspect for a poor sensor ground terminal connection at the PCM connector. Refer to Intermittents and Poor Connections Diagnosis in Wiring Systems.
  3. If you find a condition, repair the condition as necessary. Refer to Repairing Connector Terminals in Wiring Systems.

Did you find and correct the condition?

--

System OK

Go to Step 8

8
  1. Test for continuity of the Engine Oil Pressure sensor ground circuit. Refer to Testing for Continuity in Wiring Systems.
  2. If you find that the Engine Oil Pressure sensor ground circuit measures over the specified value, repair the condition as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

2ohms

System OK

Go to Step 10

9

Repair the 5.0 volt reference circuit for a short to voltage. Refer to Wiring Repairs in Wiring Systems.

Is the action complete?

--

System OK

--

10

Important:: Program the replacement PCM. Refer to Powertrain Control Module/Throttle Actuator Control Module Replacement .

Replace the PCM.

Is the action complete?

--

System OK

--

11

Important:: Before replacing the sensor inspect for poor connections.

  1. Replace the Engine Oil Pressure sensor. Refer to Engine Oil Pressure Sensor and/or Switch Replacement .
  2. Install the intake manifold. Refer to Intake Manifold Replacement in Engine Mechanical-5.7L.

Is the action complete?

--

System OK

--