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ABS Control Module -J104- / ABS Hydraulic Unit -N55-, REMOVING AND INSTALLING: Installing

GWWA45-10354Courtesy of AUDI OF AMERICA, LLC

Install in reverse order of removal and note the following:

New hydraulic control unit:

-- Attach the bracket -1- with the bolt -arrow- to 25 Nm

GWWA45-10251Courtesy of AUDI OF AMERICA, LLC

-- Carefully press the hydraulic control unit -2- in the pins -arrows- on the bracket -1-.

-- Insert the brake lines -1 and 2- into the ABS Hydraulic Unit -N55- and then install the union bolts by hand and tighten.

Fig 1: Hand Tightening Union Bolts
GWWA45-10349Courtesy of AUDI OF AMERICA, LLC

-- Connect the connector -3-.

-- After securing the brake lines to the hydraulic unit, perform output diagnostic test mode using the Vehicle Diagnostic Tester.

TIP: 

It can be determined in output diagnostic test mode, if the line connections were switched.

-- Remove the : VAG1869/2  .

-- Bleed the brake system. Refer to HYDRAULIC SYSTEM, BLEEDING .

-- If the ABS Control Module -J104- / ABS Hydraulic Unit -N55- is being replaced, select the "Replace" function for the ABS Control Module -J104- / ABS Hydraulic Unit -N55- on the Vehicle Diagnostic Tester, Guided Functions  .

CAUTION:

Faulty brakes increase the risk of an accident.

- Make sure the brakes are working correctly before driving the vehicle for the first time.

-- Install the engine/motor control module. Refer to ENGINE/MOTOR CONTROL MODULE -J623-, REMOVING AND INSTALLING 4.0L 4V TFSI or ENGINE/MOTOR CONTROL MODULE -J623-, REMOVING AND INSTALLING 2.9L; 3.0L 4V TFSI .