Combination Valve Diagnosis
Step
| Action
| Value(s)
| Yes
| No
|
DEFINITION:
Checking the mechanical operation of the combination valve warning switch.
|
1
|
- Disconnect the switch wire from the combination valve.
- Connect the jumper wire from the switch wire to ground.
- Turn the ignition switch to the ON position.
Does the brake lamp turn on?
| --
| System OK
| Go to
Step
2
|
2
| Check the brake lamp bulb.
Does the brake lamp light?
| --
| Go to
Step
4
| Go to
Step 3
|
3
| Replace the bulb.
Is the replacement complete?
| --
| Go to
Step
5
| --
|
4
| Check for an open condition in the brake lamp circuit. Refer to Wiring
Repairs in Wiring Systems.
Is the circuit repair complete?
| --
| Go to
Step
5
| --
|
5
|
- Raise the vehicle.
- Support the vehicle with safety stands
- Attach a hose to the rear bleeder screw.
- Immerse the other end of the hose in a container partly filled
with brake fluid.
- Make sure that the brake fluid level in the master cylinder is
correct.
- Turn the ignition switch to the ON position.
- Maintain moderate pressure on the brake pedal.
- Open the bleeder valve.
Does the brake lamp turn on?
| --
| Go to
Step
7
| Go to
Step 6
|
6
|
- Close the bleeder screw.
- Release the brake pedal.
- Replace the combination valve. Refer to Combination Valve Replacement.
Is the replacement complete?
| --
| System OK
| --
|
7
|
- Close the bleeder screw.
- Release the brake pedal.
- Apply moderate pressure to the brake pedal.
Does the brake lamp turn off?
| --
| Go to
Step
9
| Go to
Step 8
|
8
| Replace the combination valve. Refer to Combination Valve Replacement.
Is the replacement complete?
| --
| System OK
| --
|
9
|
- Attach a hose to the front bleeder screw.
- Immerse the other end of the hose in a container partly filled
with brake fluid.
- Make sure that the brake fluid level in the master cylinder is
correct.
- Turn the ignition switch to the ON position.
- Maintain moderate pressure on the brake pedal.
- Open the bleeder valve.
Does the brake lamp turn on?
| --
| Go to
Step
10
| Go to
Step 6
|
10
|
- Close the bleeder screw.
- Release the brake pedal.
- Apply moderate pressure to the brake pedal.
Does the brake lamp turn off?
| --
| System OK
| Go to
Step
8
|
