Parking Brake System: Adjustments

Adjusting handbrake
Perform inspection in the following manner:
When 1st tooth is engaged, no braking effect should b present.
The difference on wheel circumferential forces (left / right wheel) must not deviate from larger value by more than 30% (measured on the roller test rig).
In event of larger deviations of wheel circumferential force: Carry out readjustment.
It should be possible to hold vehicle with handbrake.
The handbrake must be readjusted whenever the actuation stroke is greater than 10 teeth.

Note: Handbrake can only be adjusted correctly if handbrake cables and all moving parts of handbrake move easily and function correctly.
Basic handbrake adjustment is necessary when:
- Replacing handbrake shoes.
- Replacing brake disks.
- Resetting adjustment unit.
- Excessive actuation stroke (10 teeth).
- Replacing handbrake Bowden cables.





1. Setting instruction for brake shoes (basic setting)
Lift out dust cover.
Release self-locking nuts on Bowden cables until tension is completely released.
Use a tubular hexagon box wrench or a long socket for this task.





Completely unscrew one wheel stud on each rear wheel.
Turn wheel until adjustment screw is visible in tapped hole.
Installation:
Install and tighten wheel bolt.






Turn adjusting screw with a screwdriver until the wheel is no longer able to turn.
Then unfasten the adjusting screw 10 notches.

2. Setting instruction for handbrake Bowden cables
After basic setting has been completed, the adjustment nuts must be uniformly hand-tightened before the Bowden cables are adjusted.
Then the handbrake lever must be tightened 5 times to approx. 400 N hand-lever force with the release button pressed.

2.1. By hand
Apply 2 teeth of handbrake lever and adjust adjusting nuts until braking action begins.
Release handbrake lever; it must be possible to turn wheels easily.
Switch ignition on; indicator light must not be on when handbrake lever is released.
1st tooth: No braking effect; indicator lamp can be lit.
2nd tooth: Braking effect must engage, indicator lamp must be lit. If the lamp is not lit, the switch contact on the handbrake lever must be adjusted.

2.2. On roller dynamometer
0th tooth (handbrake released):
Vehicles with manual transmission: Shift lever in neutral position.
Vehicles with automatic transmission: Selector lever in "N" position.
Wheel circumferential force at idle <150 N.
1st tooth: No brake force increase; indicator lamp can be lit.
2nd tooth: Indicator light must be lit.
3rd tooth: Increase in braking force.
4th tooth: Adjust handbrake Bowden cables until brake force indicator shows that >550 N has been reached.

3. Braking in duo-servo handbrake
The following braking-in procedures are applicable in case of insufficient braking effect or after replacing brake disks and/or brake shoes.

3.1. On roller dynamometer
Actuate handbrake lever until the wheel circumferential force on both wheels is at least 800 N.
Release parking brake lever after approx. 40 seconds.

3.2. When driving on road
(Where possible on factory premises or quiet road).
At approx. 40 km/h, apply handbrake lever until braking action can be felt.
Pull up handbrake lever into next catch and drive on for approx. 400 m.
A basic requirement is that handbrake is adjusted uniformly.

Note: Repeat braking-in procedure if necessary, allow brake to cool down sufficiently.