BRAKES

For every task in Brakes, the following safety requirement must be strictly enforced:

Comply with personal and environmental safety practices associated with clothing; eye protection; hand tools; power equipment; proper ventilation; and the handling, storage, and disposal of chemicals/materials in accordance with local, state, and federal safety and environmental regulations.

V. BRAKES
A. General Brake Systems Diagnosis

1. Identify and interpret brake system concern; determine necessary action. P-1

2. Research applicable vehicle and service information, such as brake system operation, vehicle service history, service precautions, and technical service bulletins. P-1

3. Locate and interpret vehicle and major component identification numbers (VIN, vehicle certification labels, calibration decals). P-1

B. Hydraulic System Diagnosis and Repair

1. Diagnose pressure concerns in the brake system using hydraulic principles (Paschal’s Law). P-1

2. Measure brake pedal height; determine necessary action. P-2

3. Check master cylinder for internal and external leaks and proper operation; determine necessary action. P-2

4. Remove, bench bleed, and reinstall master cylinder. P-1

5. Diagnose poor stopping, pulling or dragging concerns caused by malfunctions in the hydraulic system; determine necessary action. P-1

6. Inspect brake lines, flexible hoses, and fittings for leaks, dents, kinks, rust, cracks, bulging or wear; tighten loose fittings and supports; determine necessary action. P-2

7. Fabricate and/or install brake lines (double flare and ISO types); replace hoses, fittings, and supports as needed. P-2

8. Select, handle, store, and fill brake fluids to proper level. P-1

9. Inspect, test, and/or replace metering (hold-off), proportioning (balance), pressure differential, and combination valves. P-2

10. Inspect, test, and adjust height (load) sensing proportioning valve. P-3

11. Inspect, test, and/or replace components of brake warning light system. P-3

12. Bleed (manual, pressure, vacuum or surge) brake system. P-1

13. Flush hydraulic system. P-3

V. BRAKES

C. Drum Brake Diagnosis and Repair

1. Diagnose poor stopping, noise, pulling, grabbing, dragging or pedal pulsation concerns; determine necessary action. P-1
2. Remove, clean (using proper safety procedures), inspect, and measure brake drums; determine necessary action. P-1

3. Refinish brake drum. P-1

4. Remove, clean, and inspect brake shoes, springs, pins, clips, levers, adjusters/self-adjusters, other related brake hardware, and backing support plates; lubricate and reassemble. P-1

5. Remove, inspect, and install wheel cylinders. P-2

6. Pre-adjust brake shoes and parking brake before installing brake drums or drum/hub assemblies and wheel bearings. P-1

7. Install wheel, torque lug nuts, and make final checks and adjustments. P-1

V. BRAKES

D. Disc Brake Diagnosis and Repair

1. Diagnose poor stopping, noise, pulling, grabbing, dragging or pedal pulsation concerns; determine necessary action. P-1

2. Remove caliper assembly from mountings; clean and inspect for leaks and damage to caliper housing; determine necessary action. P-1

3. Clean and inspect caliper mounting and slides for wear and damage; determine necessary action. P-1

4. Remove, clean, and inspect pads and retaining hardware; determine necessary action. P-1

5. Disassemble and clean caliper assembly; inspect parts for wear, rust, scoring, and damage; replace seal, boot, and damaged or worn parts. P-2

6. Reassemble, lubricate, and reinstall caliper, pads, and related hardware; seat pads, and inspect for leaks. P-1
7. Clean, inspect, and measure rotor with a dial indicator and a micrometer; follow manufacturer’s recommendations in determining need to machine or replace. P-1

8. Remove and reinstall rotor. P-1

9. Refinish rotor according to manufacturer’s recommendations. P-1

10. Adjust calipers equipped with an integrated parking brake system. P-3

11. Install wheel, torque lug nuts, and make final checks and adjustments. P-1

V. BRAKES

E. Power Assist Units Diagnosis and Repair

1. Test pedal free travel with and without engine running; check power assist operation. P-2

2. Check vacuum supply (manifold or auxiliary pump) to vacuum-type power booster. P-2

3. Inspect the vacuum-type power booster unit for vacuum leaks; inspect the check valve for proper operation; determine necessary action. P-2

4. Inspect and test hydro-boost system and accumulator for leaks and proper operation; determine necessary action. P-3

V. BRAKES

F. Miscellaneous (Wheel Bearings, Parking Brakes, Electrica l, Etc.) Diagnosis and Repair

1. Diagnose wheel bearing noises, wheel shimmy, and vibration concerns; determine necessary action. P-1

2. Remove, clean, inspect, repack, and install wheel bearings and replace seals; install hub and adjust wheel bearings. P-1

3. Check parking brake cables and components for wear, rusting, binding, and corrosion; clean, lubricate, or replace as needed. P-2

4. Check parking brake operation; determine necessary action. P-1

5. Check operation of parking brake indicator light system. P-3
6. Check operation of brake stop light system; determine necessary action. P-1

7. Replace wheel bearing and race. P-1

8. Inspect and replace wheel studs. P-1

9. Remove and reinstall sealed wheel bearing assembly. P-2

V. BRAKES

G. Antilock Brake and Traction Control Systems

1. Identify and inspect antilock brake system (ABS) components; determine necessary action. P-1

2. Diagnose poor stopping, wheel lock-up, abnormal pedal feel or pulsation, and noise concerns caused by the antilock brake system (ABS); determine necessary action. P-2

3. Diagnose antilock brake system (ABS) electronic control(s) and components using self-diagnosis and/or recommended test equipment; determine necessary action. P-1

4. Depressurize high-pressure components of the antilock brake system (ABS). P-3

5. Bleed the antilock brake system’s (ABS) front and rear hydraulic circuits. P-2

6. Remove and install antilock brake system (ABS) electrical/electronic and hydraulic components. P-3

7. Test, diagnose and service ABS speed sensors, toothed ring (tone wheel), and circuits using a graphing multimeter (GMM)/digital storage oscilloscope (DSO) (includes output signal, resistance, shorts to voltage/ground, and frequency data). P-1

8. Diagnose antilock brake system (ABS) braking concerns caused by vehicle modifications (tire size, curb height, final drive ratio, etc.). P-3

9. Identify traction control system components. P-3