Hummer H3. Manual — part 1337

remove any air that may have been trapped in the HBCi. Refer to Antilock Brake
System Automated Bleed Procedure .

26. Turn the ignition key ON, with the engine OFF. Check to see if the brake system warning

lamp remains illuminated.

27. If the brake system warning lamp remains illuminated, refer to Symptoms - Hydraulic

Brakes.

HYDRAULIC BRAKE SYSTEM BLEEDING (PRESSURE WITH RPO BRM)

Tools Required

J 29532 Diaphragm Pressure Bleeder or equivalent. See Special Tools.

J 35589-A Master Cylinder Bleeder Adapter. See Special Tools.

J 44894-A Brake Bleeder Adapter. See Special Tools.

IMPORTANT: If the brake system warning lamp remains illuminated, DO

NOT allow the vehicle to be driven until it is diagnosed and
repaired.

CAUTION: Refer to DOT 4 BRAKE FLUID CAUTION

.

CAUTION: Refer to Brake Fluid Irritant Caution .

CAUTION: Do not remove the reservoir cap while depressing and

releasing the brake pedal. If the cap is removed while
depressing and releasing the brake pedal, pressurized brake
fluid being returned to the reservoir may leave the reservoir.
Personal injury or vehicle damage could result.

NOTE:

Refer to Brake Fluid Effects on Paint and Electrical Components
Notice .

NOTE:

When adding fluid to the brake fluid reservoir or to the clutch fluid
reservoir, use only GM Vehicle Care Brake and Clutch Fluid Super

2007 Hummer H3

2007 BRAKES Hydraulic Brakes - H3

Bleeding Procedure

1. Place a clean shop cloth beneath the brake master cylinder to prevent brake fluid spills.

2. If you disconnected the brake pipes from the master cylinder, you must perform the

following steps:

1. Ensure that the brake master cylinder reservoir is full to the maximum-fill level. If

necessary add brake and clutch fluid Super DOT-4, GM P/N 88958860 (Canadian
P/N 88901244) or equivalent DOT-4 brake fluid from a clean, sealed brake fluid
container.

If removal of the reservoir cap and diaphragm is necessary, clean the outside of the
reservoir on and around the cap prior to removal.

DOT-4, GM P/N 88958860 (Canadian P/N 88901244) or equivalent
DOT-4 brake fluid from a clean, sealed container. This polyglycol
brake fluid is hygroscopic and absorbs moisture. Do not use fluid
from an open container that may be contaminated with water.
Improper or contaminated fluid could result in damage to the
system components.

NOTE:

Do Not allow the HBCi pump and motor to run more than 1 minute
continuously. Allow 2 minutes cool down time between pump run
times. Extended pump and motor run time could create excessive
heat and damage the pump and motor assembly.

2007 Hummer H3

2007 BRAKES Hydraulic Brakes - H3

Fig. 45: View Of Master Cylinder And Brake Pipes
Courtesy of GENERAL MOTORS CORP.

2. With all the brake pipes installed securely to the master cylinder, loosen and separate

the left front brake pipe (4) from the left front port of the brake master cylinder.

3. Allow a small amount of brake fluid to gravity bleed from the open port of the master

cylinder.

4. Reconnect the brake pipe to the master cylinder port and tighten securely.

2007 Hummer H3

2007 BRAKES Hydraulic Brakes - H3

5. Have an assistant slowly depress the brake pedal fully and maintain steady pressure on

the pedal.

6. Loosen the same brake pipe to purge air from the open port of the master cylinder.

7. Tighten the brake pipe, then have the assistant slowly release the brake pedal.

8. Wait 15 seconds, then repeat steps 2.5-2.7 until all air is purged from the same port of

the master cylinder.

9. With the left front brake pipe (4) installed securely to the master cylinder, after all air

has been purged from the left front port of the master cylinder, loosen and separate the
right front brake pipe (3) from the master cylinder, then repeat steps 2.5-2.8.

10. Turn the ignition key to the ON position.

11. With the right front brake pipe (3) installed securely to the master cylinder, after all

air has been purged from the right front port of the master cylinder, loosen and
separate the right rear brake pipe (2) from the master cylinder, then repeat steps 2.5-
2.8.

12. With the right rear brake pipe (2) installed securely to the master cylinder, after all air

has been purged from the right rear port of the master cylinder, loosen and separate the
left rear brake pipe (1) from the master cylinder, then repeat steps 2.5-2.8.

13. After completing the final master cylinder port bleeding procedure, ensure that all of

the brake pipe-to-master cylinder fittings are properly tightened.

14. Turn the ignition key to the OFF position. Depress the brake pedal 20 times.

3. Fill the brake master cylinder reservoir to the maximum-fill level with brake and clutch

fluid Super DOT-4, GM P/N 88958860 (Canadian P/N 88901244) or equivalent DOT-4
brake fluid from a clean, sealed brake fluid container.

Clean the outside of the reservoir on and around the reservoir cap prior to removing the cap
and diaphragm.

4. Install the J 44894-A to the brake master cylinder reservoir. See Special Tools.

5. Check the brake fluid level in the J 29532 or equivalent. See Special Tools. Add Super

DOT-4, GM P/N 88958860 (Canadian P/N 88901244) or equivalent DOT-4 brake fluid
from a clean, sealed brake fluid container as necessary to bring the level to approximately
the half-full point.

6. Connect the J 29532 or equivalent, to the J 44894-A . See Special Tools.

7. Charge the J 29532 or equivalent, air tank to 175-205 kPa (25-30 psi). See Special Tools.

8. Open the J 29532 or equivalent, fluid tank valve to allow pressurized brake fluid to enter

the brake system. See Special Tools.

2007 Hummer H3

2007 BRAKES Hydraulic Brakes - H3