Step
| Action
| Yes
| No
|
DEFINITION: Brake fluid level is low not related to lining wear.
|
1
| Were you sent here from the Hydraulic Brake Symptom table?
| Go to
Step 2
| Go to
Diagnostic Starting Point - Hydraulic Brakes
|
2
|
- Inspect the following hydraulic brake system components for brake fluid leaks:
• | Flexible brake hose connections; threaded and bolted |
• | Flexible brake hose crimp joints |
• | Wheel cylinder piston seals, if equipped |
• | Master cylinder reservoir |
• | Master cylinder reservoir low pressure hose, if equipped |
• | Brake pressure modulator valve (BPMV) assembly, if equipped |
- Repair or replace components as necessary. Refer to
Hydraulic Brake System Diagnosis.
Did you find and correct a condition?
| Go to
Step 8
| Go to
Step 3
|
3
| Is the vehicle equipped with a vacuum brake booster?
| Go to
Step 4
| Go to
Step 6
|
4
|
- Disconnect the vacuum check valve from the booster to relieve vacuum reserve.
- Separate the master cylinder from the vacuum brake booster. Do not disconnect any brake pipes.
- Inspect the rear of the master cylinder for a brake fluid leak.
- Inspect for brake fluid in the vacuum brake booster.
Did you find a brake fluid leak?
| Go to
Step 5
| Go to
Diagnostic Starting Point - Hydraulic Brakes
|
5
| Replace the brake master cylinder and the vacuum brake booster.
Did you complete the replacement?
| Go to
Step 8
| --
|
6
|
- Wipe clean the external surface of the master cylinder to hydraulic brake booster area, if equipped.
- Separate the master cylinder from the hydraulic brake booster, if equipped. Do not disconnect any brake pipes.
- Inspect the rear of the master cylinder for a brake fluid leak.
Did you find a brake fluid leak?
| Go to
Step 7
| Go to
Diagnostic Starting Point - Hydraulic Brakes
|
7
| Replace the brake master cylinder.
Did you complete the replacement?
| Go to
Step 8
| --
|
8
|
- Install or connect components that were removed or disconnected during diagnosis.
- Road test the vehicle to confirm proper operation. Refer to
Brake System Vehicle Road Test.
Is the condition still present?
| Go to
Step 2
| System OK
|