Master cylinders manufactured by ATE, Girling and Bendix utilize 2 or 3-chamber reservoirs, a level sensor contact is built into each chamber.

A warning light is activated when brake fluid level is low or when pressure differential between two brake circuits is caused by loss of fluid in either circuit.

Floating type front disc brake calipers are used on the 190, 420 and 560 series; Not floating type calipers on other models with parking brakes are cable-actuated in rear brake rotor calipers.

All models have brake pad wear indicators and differential pressure warning indicator.

Wear sensors for 420 and 560 series operates on inner pads only.

The Anti-Lock Brake System is standard on 420SEL, 300 and 560 series (optional on 190 series).
On diesel models, a vacuum pump is incorporated to supply a vacuum to the power brake unit.

ADJUSTMENTS PEDAL HEIGHT & FREE PLAY

Pedal height measured from pedal pad to pedal stop should be 150 m.m.
to adjust loosen lock nuts and turn stop light switch until correct pedal height is obtained tighten lock nuts; pedal free play should be 5-15 m.m..

BRAKE LIGHT SWITCH
The stoplight switch is located under dash, above brake pedal loosen lock nuts and adjust switch so that contact button extends 6-8 m.m. then tighten lock nuts.

PARKING BRAKE
1. Remove only one wheel lug bolt at each rear wheel, raise vehicle.

2. Rotate wheel until lug bolt hole is positioned over parking brake adjuster,rubber grommets approximately 45 degrees forward for diagonal swing axle and 90 degrees forward for diagonal swing axle with starting torque compensation.

ADJUSTING PARKING BRAKE MECHANISM
Parking brake must be adjusted if brake pedal can be depressed by more than 2 steps of 6 without any braking effect, do not alter adjusting screw on parking brake intermediate lever; these screws are for balancing cable lengths only.

3. Using screwdriver inserted through lug bolt whole hand turn adjuster until rear wheel cannot be turned, back off the adjuster until wheel can be turned without wheel dragging.

TESTING THE BRAKE WARNING LIGHT
1. Dual warning light is mounted on dash, turn ignition on and the light should glow when parking brake lever is pulled to one notch and go off when brake lever is fully released.

2. To check circuit warning sensor, turn ignition on, release the parking brake and ensure light is off,
Open bleeder screw on one wheel and depress brake pedal and the light should light up.

3. Close bleeder screw, replenish the brake fluid and bleed system, check that light goes out after testing and if not; differential pressure pin in the master cylinder must be reset.

REMOVAL & INSTALLATION OF DISC BRAKE PADS

Removal 420SEL, 300 & 560 Series

1. Raise vehicle and remove wheels, remove upper hex head caliper bolt.

2. Pull clip of the brake pad wear sensor out of plug by opening cap on plug, rotate caliper downward and remove pads from carrier.

3. Standard front disc brake pad assembly thickness including lining backing o ring box plate is 17.5 m.m. Standard rear pad assembly thickness is 15.5 m.m..

4. Front backing plate thickness is 4.5 m.m. Rear backing plate thickness is 5mm Minimum pad thickness is 2 m.m..

Mercedes Benz Single Piston Disc Brake Caliper cleaning.

1. Using brass cylinder brush clean disc pad guide surface in caliper, siphon fluid from master cylinder to prevent overflowing press piston to bottom of bore.

2. Install disc pads and wear sensor wires, reverse removal procedure to complete installation and check that dash light goes out.

Removal All Other Mercedes Benz Models

1. Raise vehicle and remove wheels, remove cover plate from caliper and disconnect wear indicator wires.

2. Drive out retaining pins toward inside of vehicle, on Bendix brakes retaining pins have locking pins, then remove the locking pins and retaining pins then the cross spring retainers.

3. Remove disc pads from caliper, if not reusable note condition and location of pads for re installation.

4. Standard front disc brake pad assembly thickness including bearing seal lining backing plate is 17.5 m.m. Standard rear pad assembly thickness is 15 m.m..

5. Front backing plate thickness is 4.5 m.m. rear backing plate thickness is 5 m.m. minimum pad thickness is 2 m.m..

1. Using cylinder brush clean disc pad guide surface in caliper, siphon fluid from master cylinder reservoir to prevent overflowing, press pistons to bottom.

2. Mercedes Benz Disc Brake Pads.

3. Install cover plate retaining pin locking keys and wear sensor wires, check that dash light goes out, and the reset pin at master cylinder.