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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2001 🢒 Chevrolet C-Series Medium Duty Truck B7 🢒 Body and Accessories 🢒 Instrument Panel, Gauges, and Console 🢒 Engine Oil Pressure Gage Inaccurate or Inoperative

Engine Oil Pressure Gage Inaccurate or Inoperative L18 8.1L Gasoline Engine

Step

Action

Value(s)

Yes

No

Schematic Reference: Instrument Cluster Schematics

1

Did you perform the Instrument Cluster Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Instrument Cluster

2

Start the engine.

Does the engine oil pressure (EOP) gauge display that the engine oil pressure is within the specified range?

10-70 psi (69-483 kPa)

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

Go to Step 3

3
  1. Turn the ignition OFF.
  2. Disconnect the IPC.
  3. Turn the ignition ON, with the engine OFF.
  4. Connect a test lamp between the ignition 1 voltage circuit and a good ground.

Does the test light illuminate?

--

Go to Step 4

Go to Step 13

4
  1. Turn the ignition OFF.
  2. Disconnect the PCM connector C2.
  3. Turn the ignition ON, with the engine OFF.

Does the EOP gauge display at or above the specified value?

80 psi (550 kPa)

Go to Step 5

Go to Step 7

5
  1. Turn the ignition OFF.
  2. Connect a 3 amp fused jumper wire between the EOP gauge signal circuit and a good ground.
  3. Turn the ignition ON, with the engine OFF.

Does the EOP gauge display at or below the specified value?

0 psi (0 kPa)

Go to Step 8

Go to Step 6

6

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

Did you find and correct the condition?

--

Go to Step 17

Go to Step 10

7

Test the EOP gauge signal circuit for a short to ground. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 17

Go to Step 10

8
  1. Turn the ignition OFF.
  2. Disconnect the EOP sensor connector.
  3. Turn the ignition ON, with the engine OFF.
  4. Measure the voltage between EOP gauge sensor 5 volts reference circuit and the EOP gauge sensor low reference circuit.

Does the voltage measure greater than the specified?

4.6 V

Go to Step 11

Go to Step 9

9

Test the EOP gauge sensor low reference circuit for an open or for a high resistance. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 17

Go to Step 12

10

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

Did you find and correct the condition?

--

Go to Step 17

Go to Step 14

11

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

Did you find and correct the condition?

--

Go to Step 17

Go to Step 15

12

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

Did you find and correct the condition?

--

Go to Step 17

Go to Step 16

13

Repair the open, a short to ground or a high resistance in the ignition 1 voltage circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 17

--

14

Replace the IPC. Refer to Instrument Cluster Replacement .

Did you complete the replacement?

--

Go to Step 17

--

15

Replace the EOP gauge sensor. Refer to Engine Oil Pressure Sensor or Switch Replacement .

Did you complete the replacement?

--

Go to Step 17

--

16

Important: Program the replacement PCM.

Replace the PCM. Refer to Powertrain Control Module Replacement in Engine Controls - 8.1 L.

Did you complete the replacement?

--

Go to Step 17

--

17
  1. Use the scan tool in order to clear the PCM DTCs.
  2. Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2

Engine Oil Pressure Gage Inaccurate or Inoperative LG5 7.2L Diesel Engine

Step

Action

Value(s)

Yes

No

Schematic Reference: Instrument Cluster Schematics

1

Did you perform the Instrument Cluster Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Instrument Cluster

2

Start the engine.

Does the engine oil pressure (EOP) gauge display that the engine oil pressure is within the specified range?

10-70 psi (69-483 kPa)

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

Go to Step 3

3
  1. Turn the ignition OFF.
  2. Disconnect the EOP gauge sensor connector.
  3. Turn the ignition ON, with the engine OFF.

Does the EOP gauge display at or above the specified value?

80 psi (550 kPa)

Go to Step 4

Go to Step 6

4
  1. Turn the ignition OFF.
  2. Connect a 3 amp fused jumper wire between the EOP gauge sensor signal circuit and a good ground.
  3. Turn the ignition ON, with the engine OFF.

Does the EOP gauge display at or below the specified value?

0 psi (0 kPa)

Go to Step 7

Go to Step 5

5

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

Did you find and correct the condition?

--

Go to Step 12

Go to Step 9

6

Test the EOP gauge sensor signal circuit for a short to ground. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 12

Go to Step 9

7

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

Did you find and correct the condition?

--

Go to Step 12

Go to Step 8

8

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

Did you find and correct the condition?

--

Go to Step 12

Go to Step 10

9

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

Did you find and correct the condition?

--

Go to Step 12

Go to Step 11

10

Replace the EOP gauge sensor. Refer to Engine Oil Pressure Sensor or Switch Replacement .

Did you complete the replacement?

--

Go to Step 12

--

11

Replace the IPC. Refer to Instrument Cluster Replacement .

Did you complete the replacement?

--

Go to Step 12

--

12

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2