Step
| Action
| Value(s)
| Yes
| No
|
1
|
- Apply the parking brake.
- Place the ignition switch in RUN.
| --
|
Go to Step 5
|
Go to Step 2
|
2
|
- Disconnect the connector at the park brake warning switch.
- Connect a fused jumper wire between the park brake warning switch
connector or cavity B PPL(680) and ground.
Is the brake indicator illuminated?
| --
|
Go to Step 6
|
Go to Step
3
|
3
|
- Disconnect the instrument cluster connector.
- Connect a test lamp between the instrument cluster connector cavity
A6 and ground.
Does the test lamp light?
| --
|
Go to Step 4
|
Go to Step 7
|
4
|
- Disconnect the truck body control module.
- Connect a self-powered test lamp at the instrument cluster connector
cavity A6 gray(1036) wire and the truck body control module connector C1 cavity
A12.
Does the test lamp light?
| --
|
Go to Step
5
|
Go to Step 8
|
5
|
- Reconnect all components.
- Position the vehicle safely for the release of the park brake.
- Release the parking brake.
- Start the engine while observing the instrument cluster.
Is the brake indicator illuminated while the ingnition switch is in
start?
| --
|
Go to Step 9
|
Go to Step 10
|
6
| Adjust the
park brake warning switch.
Is the brake indicator illuminated?
| --
| System OK
| --
|
7
| Locate and repair
open in the ORN(240) wire between the IP fuse block and the instrument cluster.
Is the brake indicator illuminated?
| --
| System OK
| --
|
8
| Locate and repair
in GRU(1036) and Lt GRN(1037) wire between the instrument cluster and the
truck body control module.
| --
| System OK
| --
|
9
|
- Connect a self-powered test lamp between truck body control module
connector C1 cavity B10 and grouond.
- Test for continuity.
Does the test lamp light?
| --
|
Go to Step 10
|
Go to Step 11
|
10
| Replace park brake warning switch.
| --
| System OK
| --
|
11
| Locate and repair open in Lt BLU(1134) wire between the
truck body control module and the park brake warning switch.
| --
| System OK
| --
|
