LEMON Manuals: Even more car manuals for everyone
Home >> Mazda >> 1999 >> Protege DX, Automatic >> Repair and Diagnosis >> Brakes >> Traction Control >> Anti-Lock >> Component Tests >> Abs Hydraulic Unit >> On-Vehicle Inspection

On-Vehicle Inspection

NOTE: ABS CM and ABS hydraulic unit may be replaced separately.
  1. Ensure all DTCs have been cleared and battery is fully charged. See CLEARING CODES  under DIAGNOSIS & TESTING. Turn ignition switch to ON position and check if ABS warning light goes out after 2-4 seconds. If ABS warning light remains illuminated, ABS CM has detected a failure and will not activate ABS hydraulic unit. Retrieve DTCs and repair as necessary. See DIAGNOSIS & TESTING  .
  2. Turn ignition switch to OFF position. Ensure vehicle is on level surface. Raise and support vehicle on safety stands. Place transmission in Neutral. Release parking brake. Rotate wheels by hand and check for brake drag. Connect a jumper wire between DLC-1 terminals No. 13 and 20. See Figure . Depress brake pedal and have an assistant attempt to rotate right front wheel. Wheel should not rotate.
  3. With brake pedal still depressed, turn ignition switch to ON position. Brake should be momentarily released (about .5 second) and wheel should turn when pressure reduction operates. Check operation of remaining wheels using same procedure beginning with left front, right rear, then left rear wheel.
  4. If all wheels operate as specified, the following systems are operating properly:
    • Brake piping/lines to hydraulic unit.
    • Braking system, including hydraulic unit.
    • Hydraulic unit electrical system (solenoid, pump motor, etc.)
    • ABS CM output system (solenoid, relay, etc.) and harness.

    If any wheel does not operate as specified, check ABS CM input system and harness for intermittent failure. Check for fluid leakage. Repair as necessary. If input system, harness, intermittent failure or fluid leakage are not present, replace ABS hydraulic unit.