1997 Chevy Blazer 6 cyl Four Wheel Drive Automatic 184000 miles
my antilock brakes light comes on when I drive about 20 mile hwy. I changed front calipers, brakes, rotors adjusted back brakes and bled all 4 of them 3 different times and nothing seems to help, can you please please help me. Sorry I dont have a credit card but if I get the answer I will send you 20.00 guaranteed thank you sincrely kevin e-mail is graham3179@roadrunner. Com
Most common and likely to fail is a wheel sensor / wheel bearing
check the wiring at and around the wheel bearings
The Kelsey-Hayes 4-Wheel Anti-Lock (4WAL) brake system is used to prevent wheel lock-up during heavy braking. This allows driver to maintain steering control while stopping vehicle in shortest distance possible. The system consists of Brake Pressure Modulator Valve (BPMV), Vehicle Speed Sensor (VSS), Powertrain Control Module (PCM) or Vehicle Control Module (VCM), Wheel Speed Sensors (WSS), warning lights, electrical wiring and hydraulic lines.
The Electro-Hydraulic Control Unit (EHCU) is the entire unit, including the BPMV, Electronic Brake Control Module (EBCM) and combination valve. The EBCM is the electronic control portion of the ABS assembly. It is mounted on top of the BPMV located on left side of engine compartment, above fender well.
When testing and diagnosing 4WAL system, use of A scan tool is required.
An OBDII reader will not work on ABS system
The Vehicle Control Module (VCM) contains a self-diagnostic capability to detect system failures. When a DTC is set, the VCM may disable 4WAL system and illuminate ANTI-LOCK light for duration of ignition cycle. DTCs stored by VCM can be displayed using Tech 1 and appropriate cartridge.
Before diagnosing 4WAL system, perform a comprehensive visual inspection of system by checking wiring harness connectors, harness routing (pay particular attention to wheel speed sensor wiring harness routing), applicable fuses in fuse block, and ground connections. Ensure brake fluid level in master cylinder reservoir is full.