Disc Brakes System Testing
- Were you sent here from a Brake Symptom Table? If so, go to next step. If not, see DIAGNOSTIC STARTING POINT - HYDRAULIC BRAKES under TROUBLE SHOOTING.
- Visually inspect the disc brake pads for the following:
- Lining thickness.
- Uneven and/or abnormal wear (edge-to-edge and/or side-to-side).
- Evidence of contamination from an external substance.
- Looseness or damage (including pad hardware).
- Are any of the (front and/or rear) disc brake pads contaminated? If so, go to step 8 . If not, go to next step.
- Are any of the (front and/or rear) disc brake pads worn unevenly? If so, go to step 7 . If not, go to next step.
- Are any of the (front and/or rear) disc brake pads and/or pad hardware loose or damaged? If so, go to step 7 . If not, go to next step.
- Remove and inspect the worn disc brake pads for glazing, looseness, heat spots or damage. Replace the worn disc brake pads as a complete axle set. See BRAKE PADS . After completing repair, go to next step.
- Remove the (front and/or rear) disc brake calipers (as appropriate) from the mounting brackets and support the calipers. Do Not disconnect the hydraulic brake flex hoses from the calipers. See BRAKE CALIPERS
under REMOVAL & INSTALLATION. Inspect the disc brake caliper mounting bracket and the mounting/sliding hardware for the following conditions:
- Loose, bent, cracked, or damaged caliper mounting bracket.
- Binding or seized hardware.
- Worn, damaged or missing hardware components.
- Front And Rear Brake Caliper Bracket Replacement.
- Front And Rear Disc Brake Hardware Replacement.
- Inspect the disc brake calipers, brake hoses and brake pipes for evidence of an external brake fluid leak. Replace any components found to be leaking brake fluid. See REMOVAL & INSTALLATION
or OVERHAUL
for appropriate procedures.
- Front And Rear Brake Caliper Overhaul
- Front And Rear Brake Caliper Replacement
- Front And Rear Brake Hose Replacement
- Brake Pipe Replacement
- Inspect the wheel drive shaft outer seals (boots) for damage and evidence of a grease leak. Replace any wheel drive shaft seal (boot) that is found to be leaking grease which may be the source of the contamination to the pads. See appropriate FRONT SUSPENSION article. Did you find and correct the source of the leak causing contamination of the pads? If so, go to step 11 . If not, go to next step.
- Inspect the following systems for damage and evidence of an external fluid leak. Replace any faulty component.
- See appropriate STEERING - POWER RACK & PINION article.
- See appropriate ENGINE MECHANICAL article in ENGINE.
- See appropriate AUTOMATIC TRANSMISSION SERVICING article in TRANSAXLES/TRANSMISSIONS.
- Clean the remaining disc brake system components to remove any traces of the contaminant. Remove the (front and/or rear) disc brake calipers (as appropriate) from the mounting brackets and support the calipers. DO NOT disconnect the hydraulic brake flex hoses from the calipers. See BRAKE CALIPERS
under REMOVAL & INSTALLATION. Inspect the disc brake caliper mounting/sliding hardware for the following conditions:
- Binding or seized hardware.
- Distorted, worn, damaged or missing hardware components.
- Visually inspect each of the rear disc brake rotor shields/backing plates for evidence of contact with the brake rotors. Are any of the rear brake rotor shields/backing plates contacting the brake rotors? If so, go to next step. If not, go to step 14 .
- Repair or replace the rear disc brake rotor shields/backing plates as required. See DISC BRAKE BACKING PLATE under REMOVAL & INSTALLATION. After completing repair, go to next step.
- Check the thickness of each of the disc brake rotors. See BRAKE ROTOR THICKNESS MEASUREMENT in DISC BRAKE SYSTEM under ADJUSTMENTS & INSPECTIONS. Make a determination for each brake rotor if the rotor can be REFINISHED and REMAIN ABOVE the minimum requirements. Does the disc brake rotor meet the minimum requirements for REFINISHING? If so, go to next step. If not, go to step 17 .
- Inspect each of the disc brake rotors for the following surface and wear conditions:
Braking Surface Conditions
- Heavy rust and/or pitting.
- Cracks and/or heat spots.
- Excessive blueing discoloration.
Braking Surface Wear Conditions
- Deep or excessive scoring beyond maximum acceptable level.
- Lateral runout beyond maximum acceptable level.
- Thickness variation beyond maximum acceptable level.
- Rotor exhibits one or more of the Braking Surface Conditions listed previously.
- Rotor is beyond the acceptable level in one or more of the Braking Surface Wear Conditions listed previously.
- Refinish the brake rotor. See BRAKE ROTOR REFINISHING in DISC BRAKE SYSTEM under ADJUSTMENTS & INSPECTIONS. Inspect the brake rotor thickness. See BRAKE ROTOR THICKNESS MEASUREMENT in DISC BRAKE SYSTEM under ADJUSTMENTS & INSPECTIONS. Were you able to REFINISH the brake rotor within the minimum requirements? If so, go to step 20 . If not, go to step 19 .
- Is the brake rotor at or below the DISCARD requirements? If so, go to step 19 . If not, go to next step.
- Inspect each of the disc brake rotors for the following surface and wear conditions:
Braking Surface Conditions
- Heavy rust and/or pitting.
- Cracks and/or heat spots.
- Excessive blueing discoloration.
Braking Surface Wear Conditions
- Deep or excessive scoring beyond maximum acceptable level.
- Lateral runout beyond maximum acceptable level.
- Thickness variation beyond maximum acceptable level.
- Rotor exhibits one or more of the Braking Surface Conditions listed previously.
- Rotor is beyond the acceptable level in one or more of the Braking Surface Wear Conditions listed previously.
- Replace the brake rotor. See BRAKE ROTORS under REMOVAL & INSTALLATION. After completing repair, go to next step.
- Install or connect components that were removed or disconnected during diagnosis. Did you complete the operation? If so, then system should be okay. If system is not okay, go to step 2 .