MTST III: BRAKES

A. General
MHT3A001 Research vehicle service information, including fluid type, vehicle service history, service precautions, and technical service bulletins.
MHT3A002 Identify brake system components and configurations (including air and hydraulic systems, parking brake, power assist, and vehicle dynamic brake systems).
MHT3A003 Identify brake performance problems caused by the mechanical/foundation brake system (air and hydraulic).
MHT3A004 Use appropriate electronic service tool(s) and procedures to diagnose problems; check, record, and clear diagnostic codes; interpret digital multimeter (DMM) readings.
B. Air Brakes: Air Supply and Service Systems
MHT3B001a Inspect, test, repair, and/or replace air supply system components such as compressor, governor, air drier, tanks, and lines; inspect service system components such as lines, fittings, mountings, and valves (hand brake/trailer control, brake relay, quick release, tractor protection, emergency/spring brake control/modulator, pressure relief/safety); determine needed action.
MHT3B001a Inspect, test, repair, and/or replace air supply system components such as compressor, governor, air drier, tanks, and lines; inspect service system components such as lines, fittings, mountings, and valves (hand brake/trailer control, brake relay, quick release, tractor protection, emergency/spring brake control/modulator, pressure relief/safety); determine needed action.
MHT3B001b Inspect, test, repair, and/or replace air supply system components such as compressor, governor, air drier, tanks, and lines; inspect service system components such as lines, fittings, mountings, and valves (hand brake/trailer control, brake relay, quick release, tractor protection, emergency/spring brake control/modulator, pressure relief/safety); determine needed action.
MHT3B001c Inspect, test, repair, and/or replace air supply system components such as compressor, governor, air drier, tanks, and lines; inspect service system components such as lines, fittings, mountings, and valves (hand brake/trailer control, brake relay, quick release, tractor protection, emergency/spring brake control/modulator, pressure relief/safety); determine needed action.
MHT3B001d Inspect, test, repair, and/or replace air supply system components such as compressor, governor, air drier, tanks, and lines; inspect service system components such as lines, fittings, mountings, and valves (hand brake/trailer control, brake relay, quick release, tractor protection, emergency/spring brake control/modulator, pressure relief/safety); determine needed action.
MHT3B001e Inspect, test, repair, and/or replace air supply system components such as compressor, governor, air drier, tanks, and lines; inspect service system components such as lines, fittings, mountings, and valves (hand brake/trailer control, brake relay, quick release, tractor protection, emergency/spring brake control/modulator, pressure relief/safety); determine needed action.
MHT3B001f Inspect, test, repair, and/or replace air supply system components such as compressor, governor, air drier, tanks, and lines; inspect service system components such as lines, fittings, mountings, and valves (hand brake/trailer control, brake relay, quick release, tractor protection, emergency/spring brake control/modulator, pressure relief/safety); determine needed action.
MHT3B001g Inspect, test, repair, and/or replace air supply system components such as compressor, governor, air drier, tanks, and lines; inspect service system components such as lines, fittings, mountings, and valves (hand brake/trailer control, brake relay, quick release, tractor protection, emergency/spring brake control/modulator, pressure relief/safety); determine needed action.
MHT3B002a Test gauge operation and readings; test low pressure warning alarm operation; perform air supply system tests such as pressure build-up, governor settings, and leakage; drain air tanks and check for contamination; determine needed action.
MHT3B002b Test gauge operation and readings; test low pressure warning alarm operation; perform air supply system tests such as pressure build-up, governor settings, and leakage; drain air tanks and check for contamination; determine needed action.
MHT3B002c Test gauge operation and readings; test low pressure warning alarm operation; perform air supply system tests such as pressure build-up, governor settings, and leakage; drain air tanks and check for contamination; determine needed action.
MHT3B002d Test gauge operation and readings; test low pressure warning alarm operation; perform air supply system tests such as pressure build-up, governor settings, and leakage; drain air tanks and check for contamination; determine needed action.
MHT3B003 Demonstrate knowledge and understanding of air supply and service system components and operations.
MHT3B004 Inspect air compressor drive gear components (gears, belts, tensioners, and/or couplings); determine needed action.
MHT3B005 Inspect air compressor inlet; inspect oil supply and coolant lines, fittings, and mounting brackets; repair or replace as needed.
MHT3B006 Inspect and test air tank relief (safety) valves, one-way (single) check valves, two-way (double) check valves, manual and automatic drain valves; determine needed action.
MHT3B007 Inspect and clean air drier systems, filters, valves, heaters, wiring, and connectors; determine needed action.
MHT3B008 Inspect and test brake application (foot/treadle) valve, fittings, and mounts; check pedal operation; determine needed action.
C. Air Brakes: Mechanical/Foundation Brake System
MHT3C001 Inspect, test, repair, and/or replace service brake chambers, diaphragms, clamps, springs, pushrods, clevises, and mounting brackets; determine needed action.
MHT3C002 Identify slack adjuster type; inspect slack adjusters; perform needed action.
MHT3C003 Check camshafts (S-cam), tubes, rollers, bushings, seals, spacers, retainers, brake spiders, shields, anchor pins, and springs; perform needed action.
MHT3C004 Inspect rotor and mounting surface; measure rotor thickness, thickness variation, and lateral runout; determine needed action.
MHT3C005 Inspect, clean, and adjust air disc brake caliper assemblies; inspect and measure disc brake pads; inspect mounting hardware; perform needed action.
MHT3C006a Remove brake drum; clean and inspect brake drum and mounting surface; measure brake drum diameter; measure brake lining thickness; inspect brake lining condition; determine needed action.
MHT3C006b Remove brake drum; clean and inspect brake drum and mounting surface; measure brake drum diameter; measure brake lining thickness; inspect brake lining condition; determine needed action.
MHT3C007 Diagnose concerns related to the mechanical/foundation brake system including poor stopping, brake noise, premature wear, pulling, grabbing, or dragging; determine needed action.
D. Air Brakes: Parking Brake System
MHT3D001 Inspect, test, and/or replace parking (spring) brake chamber.
MHT3D002 Inspect, test, and/or replace parking (spring) brake check valves, lines, hoses, and fittings.
MHT3D003 Inspect, test, and/or replace parking (spring) brake application and release valve.
MHT3D004 Manually release (cage) and reset (uncage) parking (spring) brakes.
MHT3D005 Identify and test anti-compounding brake function; determine needed action.
E. Hydraulic Brakes: Hydraulic System
MHT3E001 Check master cylinder fluid level and condition; determine proper fluid type for application.
MHT3E002 Inspect hydraulic brake system for leaks and damage; test, repair, and/or replace hydraulic brake system components.
MHT3E003 Check hydraulic brake system operation including pedal travel, pedal effort, and pedal feel; determine needed action.
MHT3E004 Diagnose poor stopping, premature wear, pulling, dragging, imbalance, or poor pedal feel caused by problems in the hydraulic system; determine needed action.
MHT3E005 Test master cylinder for internal/external leaks and damage; replace as needed.
MHT3E006 Test metering (hold-off), load sensing/proportioning, proportioning, and combination valves; determine needed action.
MHT3E007 Test brake pressure differential valve; test warning light circuit switch, bulbs/LEDs, wiring, and connectors; determine needed action.
MHT3E008 Bleed and/or flush hydraulic brake system.
F. Hydraulic Brakes: Mechanical/Foundation Brake System
MHT3F001 Clean and inspect rotor and mounting surface; measure rotor thickness, thickness variation, and lateral runout; determine necessary action.
MHT3F002a Inspect and clean disc brake caliper assemblies; inspect and measure disc brake pads; inspect mounting hardware; perform needed action.
MHT3F002b Inspect and clean disc brake caliper assemblies; inspect and measure disc brake pads; inspect mounting hardware; perform needed action.
MHT3F003 Remove, clean and inspect brake drums; measure brake drum diameter; measure brake lining thickness; inspect brake lining condition; inspect wheel cylinders; determine serviceability.
MHT3F004 Check disc brake caliper assembly mountings and slides; replace as needed.
G. Hydraulic Brakes: Parking Brake System
MHT3G001 Check parking brake operation; inspect parking brake application and holding devices; adjust, repair, and/or replace as needed.
H. Power Assist Systems
MHT3H001 Check brake assist/booster system (vacuum or hydraulic) hoses and control valves; check fluid level and condition (if applicable).
MHT3H002 Check operation of emergency (back-up/reserve) brake assist system.
MHT3H003 Identify concerns related to the power assist system (vacuum or hydraulic), including stopping problems caused by the brake assist (booster) system; determine needed action.
MHT3H004 Inspect, test, repair, and/or replace hydraulic brake assist/booster systems, hoses, and control valves.
I. Vehicle Dynamic Brake Systems (Air and Hydraulic): Antilock Brake System (ABS), Automatic Traction Control (ATC) System, and Electronic Stability Control (ESC) System
MHT3I001 Observe antilock brake system (ABS) warning light operation including trailer and dash mounted trailer ABS warning light; determine needed action.
MHT3I002 Observe automatic traction control (ATC) and electronic stability control (ETC) warning light operation; determine needed action.
MHT3I003 Identify stopping concerns related to the vehicle dynamic brake systems: ABS, ATC, and ESC; determine needed action.
MHT3I004 Diagnose problems in the vehicle dynamic brake control systems; determine needed action.
MHT3I005 Check and test operation of vehicle dynamic brake system (air and hydraulic) mechanical and electrical components; determine needed action.
MHT3I006 Test vehicle/wheel speed sensors and circuits; adjust, repair, and/or replace as needed.
MHT3I007 Bleed ABS hydraulic circuits.
MHT3I008 Verify power line carrier (PLC) operation.
J. Wheel Bearings
MHT3J001 Clean, inspect, lubricate, and/or replace wheel bearings and races/cups; replace seals and wear rings; inspect spindle/tube; inspect and replace retaining hardware; adjust wheel bearings; check hub assembly fluid level and condition; verify end play with dial indicator method.
MHT3J002 Identify, inspect, and/or replace unitized/preset hub bearing assemblies.