ABS (Anti-Lock Brake System)
ABS BLEEDING INFORMATIONWARNING:
- THE PUMP IN THE ABS, WHEN OPERATING, PRODUCES HIGH BRAKE FLUID PRESSURE THROUGHOUT THE BRAKE SYSTEM. IT IS IMPORTANT THAT ALL FLUID CONNECTORS BE SECURE BEFORE ALLOWING THE PUMP MOTOR TO OPERATE. THIS PRESSURE SUBSIDES QUICKLY WHEN THE PUMP MOTOR SHUTS OFF AND IS OF NO CONCERN DURING MOST ABS SERVICING. BE CAUTIOUS, HOWEVER, WHEN BREAKING A FLUID CONNECTION IMMEDIATELY AFTER THE PUMP MOTOR HAS OPERATED. RESIDUAL PRESSURE MAY BE PRESENT.
- BRAKE FLUID CONTAINS POLYALKALENE GLYCOL ETHERS. AVOID CONTACT WITH EYES. WASH HANDS THOROUGHLY AFTER HANDLING. IF BRAKE FLUID CONTACTS EYES, FLUSH WITH RUNNING WATER FOR 15 MINUTES. GET MEDICAL ATTENTION IF IRRITATION PERSISTS. IF TAKEN INTERNALLY, DRINK WATER AND INDUCE VOMITING. GET MEDICAL ATTENTION IMMEDIATELY.
CAUTION:
- When any part of the hydraulic brake system has been disconnected for repair or replacement, air may get into the lines and cause spongy, unsafe pedal action. This requires the bleeding of the brake system to ensure that all air is expelled from the brake cylinders and lines. The brake system can be bled manually or with pressure-bleeding equipment, such as a brake bleeder. Pressure bleeding is the preferred method.
- Bleed one wheel at a time. Start the bleeding at the right rear wheel and then the left rear wheel. Proceed to bleed the front brakes, starting with the right front brake. Finish bleeding at the left front brake. Keep the master cylinder reservoir filled with SAE J1703 DOT 3 or DOT 4 brake fluid.
- Never reuse brake fluid that has been drained from the system.
1. Bleed the anti-lock brake system as follows:
a. The master cylinder and Hydraulic Control Unit (HCU) must be bled using the Special Service Tool (SST) anti-lock brake-system harness adapter or equivalent). If this procedure is not followed, air will be trapped in the HCU, which eventually leads to a spongy brake pedal.
b. The remaining brake lines can be bled in the conventional manner, either manually or with pressure.
2. To bleed the master cylinder and HCU, disconnect the 55-pin harness connector from the ABS Control Unit and connect the anti-lock brake adapter to the harness connector.
a. Place the bleed/harness switch in the BLEED position. At this point, the red OFF indicator should illuminate.
b. Turn the ignition switch ON.
c. Push the START button on the adapter. This starts the pump motor. The red OFF indicator turns off and the green ON indicator illuminates. The pump motor will run for 60 seconds once the START button is pushed.
- You do not need to hold the START button down.
- If the pump motor must be turned off for any reason before the 60 seconds have elapsed, push the ABORT button.
d. After the first 20 seconds have passed, push and hold the VALVES button for 20 seconds. The green ON indicator will remain on. This bleeds any trapped air from the master cylinder and HCU. The pump will continue to run for an additional 20 seconds after the VALVES button is released.
e. Sixty seconds after the START button is pushed, the green ON indicator will go off and the red OFF indicator will illuminate.
f. After the red OFF indicator illuminates, turn the ignition to OFF, disconnect the harness connector from the adaptor and reconnect it to the ABS Control Unit.
g. Bleed the brake lines in the conventional manner.
Bleed the lines in the following order:
1st Right rear
2nd Left front
3rd Left rear
4th Right front