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Makes 🢒 Isuzu 🢒 2002 🢒 Isuzu T-Series (Truck Line C) 🢒 Brakes 🢒 Park Brake 🢒 Park Brake Indicator Inoperative

Park Brake Indicator Inoperative Exc. Electro-Hydraulic Parking Brake

Step

Action

Yes

No

Schematic Reference: Park Brake System Schematics

1

Did you review the Park Brake Description and Operation?

Go to Step 2

Go to Diagnostic System Check - ABS

2
  1. Disconnect the Park Brake Relay harness connector.
  2. Connect a fused jumper wire from the park brake indicator control circuit to a good ground. Refer to Using Fused Jumper Wires in Wiring Systems.

Does the PARK BRAKE indicator illuminate?

Go to Step 7

Go to Step 3

3
  1. Disconnect from the instrument panel cluster, the harness connector containing the ignition 1 voltage circuit.
  2. Test the ignition 1 voltage circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 4

4

Test the park brake indicator control circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 5

5

Inspect the PARK BRAKE indicator bulb for an open, burned out, filament.

Did you find and correct the condition?

Go to Step 14

Go to Step 6

6

Replace the instrument panel cluster. Refer to Instrument Cluster Replacement in Instrument Panel, Gages, and Console.

Did you complete the replacement?

Go to Step 14

--

7

Test the control side ground circuit of the park brake relay for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 8

8

Test the coil side ground circuit of the park brake relay for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 9

9
  1. Connect a test lamp from the park brake relay control circuit to a good ground.
  2. Release the park brake.

Does the test lamp illuminate?

Go to Step 11

Go to Step 10

10
  1. Disconnect the park brake switch harness connector.
  2. Test the park brake relay control circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 12

11

Replace the park brake relay. Refer to Park Brake Relay Replacement .

Did you complete the replacement?

Go to Step 14

--

12

Test the ignition 1 voltage circuit of the park brake relay for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 13

13

Replace the park brake switch. Refer to Parking Brake Indicator Switch Replacement .

Did you complete the replacement?

Go to Step 14

--

14

Operate the system to verify the repair.

Does the system operate properly?

System OK

Go to Step 2

Park Brake Indicator Inoperative Electro-Hydraulic Parking Brake

Circuit Description

The PBCM illuminates the PARK BRAKE indicator when the parking brake is applied. The PBCM illuminates the indicator by applying ground to the lamp.

Diagnostic Aids

Thoroughly inspect connections or circuitry that may cause an intermittent malfunction. Refer to the following:

    •  Testing for Electrical Intermittents
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs
    •  Connector Repairs

Test Description

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

  1. The PBCM may be damaged if the park brake indicator control circuit is shorted to voltage.

Step

Action

Yes

No

Schematic Reference: Park Brake System Schematics

1

Did you perform the Parking Brake Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Park Brake

2
  1. Turn ON the ignition.
  2. Apply the parking brake.

Does the PARK BRAKE indicator turn ON?

Go to Diagnostic Aids

Go to Step 3

3
  1. Turn OFF the ignition.
  2. Disconnect from the instrument panel cluster, the harness connector containing the park brake indicator control circuit. Refer to Instrument Cluster Replacement in Instrument Panel, Gages, and Console.
  3. Turn ON the ignition.
  4. Connect a test lamp between the battery positive voltage circuit and the park brake indicator control circuit.

Does the test lamp illuminate?

Go to Step 4

Go to Step 5

4

Inspect the PARK BRAKE indicator lamp for an open filament.

Did you find and correct the condition?

Go to Step 10

Go to Step 6

5

  1. Disconnect from the PBCM, the harness connector containing the park brake indicator control circuit.
  2. Test the park brake indicator control circuit for an open 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 8

6

Inspect for poor connections at the harness connector of the instrument panel cluster. 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 7

7

Replace the instrument panel cluster. Refer to Instrument Cluster Replacement in Instrument Panel, Gages, and Console.

Did you complete the replacement?

Go to Step 10

--

8

Inspect for poor connections at the harness connector of the PBCM. 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

9

Replace the PBCM. Refer to Park Brake Control Module Replacement .

Did you complete the replacement?

Go to Step 10

--

10
  1. Turn ON the ignition.
  2. Ensure the parking brake is applied.

Does the PARK BRAKE indicator turn ON?

System OK

Go to Step 3