For 1990-2009 cars

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 | --
2 |

1. Inspect the following hydraulic brake system components for brake fluid leaks:

• | Flexible brake hose connections; threaded and bolted

• | Flexible brake hose crimp joints

• | Brake pipe fittings

• | Caliper piston seals

• | 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

2. 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 |

1. Disconnect the vacuum check valve from the booster to relieve vacuum reserve.
2. Separate the master cylinder from the vacuum brake booster. Do not disconnect any brake pipes.
3. Inspect the rear of the master cylinder for a brake fluid leak.
4. Inspect for brake fluid in the vacuum brake booster.

Did you find a brake fluid leak?

Go to Step 5

--

5 | Replace the brake master cylinder and the vacuum brake booster. Did you complete the replacement? | Go to Step 8 | --
6 |

1. Wipe clean the external surface of the master cylinder to hydraulic brake booster area, if equipped.
2. Separate the master cylinder from the hydraulic brake booster, if equipped. Do not disconnect any brake pipes.
3. Inspect the rear of the master cylinder for a brake fluid leak.

Did you find a brake fluid leak?

Go to Step 7

--

7 | Replace the brake master cylinder. Did you complete the replacement? | Go to Step 8 | --
8 |

1. Install or connect components that were removed or disconnected during diagnosis.
2. 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