GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Was the Hydraulic Brake System Diagnostic Check performed?

--

Go to Step 2

Go to Hydraulic Brake Diagnostic System Check

2

Perform the Accumulator Leak-Down test. Refer to Accumulator Leak-Down Test .

Did the accumulator pass the leak-down test?

--

Go to Step 4

Go to Step 3

3

Replace the accumulator. Refer to Hydraulic Brake Booster Accumulator Replacement .

Is the repair complete?

--

Go to Step 7

--

4

Inspect the following power steering system components for contamination:

    • The power steering gear
    • The power steering pump
    • The hydraulic brake booster
    • The power steering hoses

Is the power steering system fluid contaminated?

--

Go to Step 5

Go to Step 6

5

  1. Flush the power steering system. Refer to Power Steering System Flushing in Power Steering System.
  2. Replace the hydraulic brake booster. Refer to Power Brake Booster Replacement .

Is the repair complete?

--

Go to Step 7

--

6

Replace the hydraulic brake booster. Refer to Power Brake Booster Replacement .

Is the repair complete?

--

Go to Step 7

--

7

Verify proper brake system operation.

Does the original condition still exist?

--

Verify customer complaint. Begin diagnosis again. Go to Step 1.

Go to Hydraulic Brake Diagnostic System Check