S15/T15 Sonoma P/U 2WD V6-262 4.3L VIN W CPI (1994)
9. Check the master cylinder reservoir fluid level and fill if needed.
10. With the ignition switch "ON" and the engine off, do six function tests with the Tech-1 scan tool.
11. Repeat the wheel cylinder and caliper bleed procedure to remove the air that purged from the BPMV during the tunction tests.
12. Apply firm pressure to the brake pedal and evaluate brake pedal feel.
13. Repeat the bleed procedure if needed.
- Make sure you have a good, hard brake pedal before starting the engine and moving the vehicle.
With Rear Wheel Antilock Brake System
REAR WHEEL ANTILOCK BRAKE SYSTEM BLEEDING
NOTICE: The ignition switch must be in the "OFF" position or false DTCs could be set to memory.
Tools Required:
- J 39177 Combination Valve Pressure Bleeding Tool
- TK 00000 Tech-1 Scan Tool
- TK 02650 RWALI4WAL Cartridge Kit or 7000001 Mass Storage Cartridge
1. Install J 39177 on the combination valve.
2. Check the master cylinder reservoir fluid level and fill it needed.
3. Bleed wheel cylinders and calipers.
4. Turn ignition switch "ON" and do three function tests with the Tech-1 scan tool.
5. Re-bleed the rear brakes as described under Pressure Bleeding.
6. Evaluate brake pedal feel.
7. Repeat the bleed procedure if needed.
Hydraulic System Flushing
HYDRAULIC SYSTEM FLUSHING
Flushing is done at each bleeder valve similar to the bleeding procedure. The difference-is that the bleeder valve is opened 1 1/2 turns and fluid is
forced through the pipes, hoses, and bleeder valves until it comes out clear in color. Refer to Hydraulic System, Service and Repair.
Check the master cylinder fluid level after flushing at each bleeder valve and refill as required. After flushing, make sure the master cylinder reservoir
is filled to the correct level.
Manual Bleeding
MANUAL BLEEDING
NOTICE: Brake fluid will damage electrical connections and painted surfaces. Use shop cloths, suitable containers, and tender covers to prevent
brake fluid from contacting these areas. Always re-seal and wipe off brake fluid containers to prevent spills.
Tool Required: J 28434 Wheel Cylinder Bleeder Wrench
- Relieve the vacuum reserve by applying the brakes several times with the ignition "OFF"
1. Fill the master cylinder reservoirs with Delco Supreme No. 11 Hydraulic Brake Fluid (GM P/N 1052535) or an equivalent DOT 3 motor vehicle
brake fluid.
- Maintain the fluid level during bleeding.
2. If the master cylinder is suspected to have air in the bore, bleed it before any wheel cylinder or caliper.
A. Disconnect the forward brake pipe connection at the master cylinder.
B. Allow the brake fluid to flow from the connector port.
C. Connect the brake pipe but do not tighten.
D. Slowly apply the brake pedal and allow the air to bleed from the loose fitting.
E. Tighten the fitting before releasing the pedal.
F. Wait 15 seconds.
G. Repeat this sequence, including the 15-second wait, until all air is purged from the bore.
H. After all air has been removed from the forward connection, repeat this procedure for the rear pipe.
3. If the BPMV of the 4WAL system is replaced or suspected to have air trapped inside, it must be bled next. Refer to With ABS.
4. Bleed each wheel in the following sequence:
