Brake Lines, Brake Hoses: Brake Lining Wear Indicator

• Brake lines and brake hoses must be correctly routed and must not abut with body or components in a way which would cause chafing.
• To prevent damage, release and tighten brake line couplings with a special brake line wrench only.
• The system must be bled each time any brake lines have been detached.
• All connection points must be checked for leaks.
• Only tighten down brake hoses on the front axle when wheels are in straight-ahead position.
• Close open connections on brake lines and individual components to prevent dirt from entering the brake system.
• Observe tightening torques when tightening down brake line screw connections.

Tightening torque, refer to 34 32 1AZ in BRAKES - TIGHTENING TORQUES - 645CI .

Wheel-slip control system: 

The slip control system is basically maintenance-free. However, be sure to adhere to the following:

• When carrying out welding work with electric welding equipment, be sure to disconnect the plug from the electronic control unit (ignition turned off).
• During painting work, the control unit may be subjected for brief periods to loads of max. 95°C and for long periods (approx. 2 hours) to loads of max. 85°C.
• Tighten down the battery terminals completely.
• The brake lines on the hydraulic unit must not be mixed up; if necessary, mark them before they are removed and after completing repairs perform the mix-up check with the DIS Tester.