ABS Hydraulic Unit -N55- WITH ABS Control Module -J104-: Installing

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Installation is the reverse of removal, with special attention to the following:

NOTE:

For customer service, the ABS hydraulic unit -- is filled with brake fluid.

Remove the sealing plugs on the new ABS hydraulic unit -- when the corresponding brake line is going to be installed.

If the sealing plugs are removed from the ABS hydraulic unit -- before installing the corresponding brake line, the brake fluid will drain. If that is the case, sufficient brake system bleeding can no longer be ensured.

NOTE:

All the rubber buffers must be inserted in the bracket.

-- Press the ABS hydraulic unit -- with the ABS control module -- down into the bracket in the vehicle.

NOTE:

When pressing the ESP control unit into the bracket, counterhold the rubber buffers so they do not fall through.

-- Connect the brake lines according to the markings.

WARNING:

If the brake line connectors are replaced, an ABS/ESP system malfunction will register.

NOTE:

By performing the output check diagnosis, it can be determined if the line connections were interchanged.

-- Tighten all the brake lines -arrow- on the ABS hydraulic unit --.

Fig 1: Identifying Brake Lines

Courtesy of AUDI OF AMERICA, LLC

Component	Nm
All brake lines to the hydraulic unit	14

-- Connect the electrical connector on the ABS control module --.

-- Press the locking bracket down until it engages audibly.

-- Press the securing clip -1- down and engage it.

Fig 2: Identifying Brake Lines

Courtesy of AUDI OF AMERICA, LLC

-- Remove the VAG 1869/2.

-- Bleed the brake system.

-- After securing the brake lines on the ABS hydraulic unit --, perform output diagnostic test mode.

NOTE:

By performing the output check diagnosis, it can be determined if the line connections were interchanged.

Use thevehicle diagnostic tester for this.

If ABS hydraulic unit -- was replaced, it must be coded.

Use the vehicle diagnostic tester for this.

-- On display, select:

Chassis
Brake System
01 - On Board Diagnostic (OBD) capable systems
03 - Brake electronics

-- Select the following functions on the display:

ABS hydraulic unit --
ABS hydraulic unit --, functions
ABS hydraulic unit -- Coding control module

The following sensors should also be calibrated after replacing ABS control module --.

Steering angle sensor -G85-
Transverse acceleration sensor -G200-
Longitudinal acceleration sensor -G251-

Use the vehicle diagnostic tester for this.

-- On display, select:

Chassis
Brake System
01 - On Board Diagnostic (OBD) capable systems
03 - Brake electronics

-- Select the following functions on the display:

ABS hydraulic unit --
ABS hydraulic unit --, functions.

-- Then perform the ESP driving and system test.