Precautions for vehicles with ABS (VW Passat B4)

When removing the battery for electric welding, it is necessary to disconnect the plug connector from the electronic control unit with the ignition off.

When carrying out painting work, the electronic control unit must not be exposed to temperatures of 85°C for more than 2 hours.

When carrying out work on the brake system, ensure that the brake lines are laid correctly and follow the rules for bleeding the brakes.

Ensure that the wire ends are securely connected to the battery terminals.

To remove and install the hydraulic unit, turn off the ignition. Relieve pressure in the ABS system. Disconnect the wire from the negative terminal of the battery. Remove the protective cover of the hydraulic unit. Disconnect the plug and ground jumper from the hydraulic unit. Remove the fluid from the hydraulic unit reservoir with a syringe. Disconnect the pipes from the hydraulic unit and plug the pipe openings. Remove the storage shelf on the driver's side. Remove the brake pedal pusher axle. Unscrew the hydraulic unit mounting nuts. Remove the hydraulic unit, take out the rubber seal.

Note: Do not move the pushrod of the removed hydraulic unit.

Install the hydraulic unit in the reverse order of removal and bleed air from the brake hydraulic system as indicated below.