Hydraulic Control Assembly - Antilock Brakes: Service and Repair

Hydraulic unit brake system

Note! The illustrations in this service information are used for different model years and/or models. Some variation may occur. However, the essential information in the illustrations is always correct.

Preparatory work




Secure the pedal in the depressed position. Use a pedal jack.
Remove the protective cap from the bleed nipple at the left front wheel. Install a plastic hose on the nipple. Open the bleed nipple. Collect the brake fluid in a container.
Shut the bleed nipple.




Ignition off.

Remove:
- the battery. Removal and Replacement
- the 3 screws (1)
- the battery box (2).

Removal

Removing the splash guards




Remove the 3 clips holding the cowl.




Carefully lift up the cowl. Remove the 2 clips for the protective cover.
Remove the protective cover over the brake fluid reservoir.





Remove:
- the plastic nut
- the upper protective cover for the firewall.

Removing the brake pipe





Note! Clean the brake tube terminals at the master cylinder and anti-lock brake system unit. Place paper under the master cylinder. This is to protect the paintwork from damage if brake fluid is spilled.

Remove:
- the two brake tubes (1) between the master cylinder and the control module
- the two brake tubes (2).
Detach the two brake pipes (3) from the hydraulic modulator.

Note! Note the position of the brake tubes in the hydraulic modulator. Install plugs on the brake tubes and the master cylinder.

Removing the hydraulic modulator





Remove:
- the connector from the brake control module (BCM)
- 1 screw.
Pull the hydraulic modulator to one side. Remove the hydraulic modulator.





Remove:
- the 2 screws for the bracket
- the bracket from the hydraulic modulator.

Note! Working with the hydraulic modulator requires a very clean environment. The hydraulic modulator must not be opened under any circumstances. When removing the brake control module (BCM), see: Anti-lock Brake System Module (ABS) Anti-Lock Brake System Module (ABS).

Installation

Note! For tightening torques, see Specifications. Tightening Torque.

Installing the hydraulic modulator

Note! The ABS hydraulic modulator is filled with brake fluid. It is important that the plugs are not removed until the brake tubes are to be connected.

Install:
- the bracket
- the 2 screws.




- the hydraulic modulator
- the 1 M6 screw
- the connector on the brake control module (BCM).

Installing the brake pipes





Install:
- the two brake pipes (3). Tighten. See: Tightening torque Tightening Torque
- the two brake tubes (1) between the master cylinder and the control module
- the two brake tubes (2).

Bleeding brake systems
Remove the pedal jack.
Bleed the brake system. See: Brake system bleeding Brake System Bleeding.
Check that the brake pipe connections are sealed.
Check the brake fluid level.

Installing the protective covers





Install
- the protective cover for the firewall
- the plastic nut.




Install the protective cover over the brake fluid reservoir.
Carefully lift up the cowl. Install the 2 clips for the protective cover.




Install the 3 clips holding the cowl.

Installing the battery





Install:
- the battery box (2)
- the 3 M6 screws (1)
- the battery as shown: Battery Removal and Replacement.

Ordering software

Note! When replacing the hydraulic modulator, new software must be programmed into the brake control module (BCM).

Order applicable software. Programming and Relearning






Calibrating the control module

Note! Only applies to control modules with DSTC function.

Use VIDA vehicle communication to calibrate the control module

Finishing

Final check
Ignition on.
Wait five seconds and until the symbol for the brakes on the dashboard has gone out.
In the event of a fault (the symbol is lit).
Check that the connector is connected.
Read off any diagnostic trouble codes (DTCs) stored in the control module.
Erase. Interrupt the diagnostic function by turning off the ignition.
Test drive the car, see: Test Drive Form (ABS), description Test Drive Form (ABS), Description.
Check that no diagnostic trouble codes (DTCs) are stored.
Interrupt the diagnostic function by turning off the ignition.