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Home >> Audi >> 2017 >> A3 Premium, 2D Convertible >> Repair and Diagnosis >> Brakes >> Traction Control >> Antilock Brake System >> 45 Antilock Brake System >> Control Module And Hydraulic Unit >> ABS Control Module -J104- /ABS Hydraulic Unit -N55-, REMOVING AND INSTALLING >> ABS Control Module -J104- AND ABS Hydraulic Unit -N55-, REMOVING AND INSTALLING, VEHICLES WITH DIESEL ENGINE AND AWD >> Installing
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ABS Control Module -J104- AND ABS Hydraulic Unit -N55-, REMOVING AND INSTALLING, VEHICLES WITH DIESEL ENGINE AND AWD: Installing

Install in the reverse order of removal while noting the following:

-- Place the hydraulic control unit at the bottom of the engine compartment and secure it from falling down.

-- Install the mounting bracket for the hydraulic control module in the vehicle.

-- Push the hydraulic control module -1- with the bracket into the pins in the engine compartment in the direction of -arrows-.

GWWA45-10183Courtesy of AUDI OF AMERICA, LLC
NOTE:

The hydraulic control module must rest in all pins.

Only remove the plugs on the new hydraulic unit if the corresponding brake line is installed.

If the plugs are removed too early from the hydraulic unit, brake fluid can escape and the unit may not be sufficiently filled or adequately bled.

When installing the hydraulic control module, make sure the rubber buffer is not pushed out of the bracket.

Identification of the hydraulic unit.

Fig 1: Hydraulic Unit Brake Line Installation Sequence
GWWN45-10244Courtesy of AUDI OF AMERICA, LLC

A -

Hydraulic Unit To Master Brake Cylinder Primary Piston Circuit -HZ2-

B -

Hydraulic Unit To Master Cylinder Secondary Piston Circuit -HZ1-

1 -

Hydraulic Unit To Right Front Brake Caliper -VR-

2 -

Hydraulic Unit To Left Rear Brake Caliper -HL-

3 -

Hydraulic Unit To Right Rear Brake Caliper -HR-

4 -

Hydraulic Unit To Left Front Brake Caliper -VL-

-- Insert all brake lines into the ABS Hydraulic Unit -N55-, install all union bolts by hand and tighten in the sequence -1 through 6-.

Fig 2: Brake Line Tightening Sequence
GWWN45-10263Courtesy of AUDI OF AMERICA, LLC

-- Remove the Brake Pedal Actuator: 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, Guided Functions  .

CAUTION:

Risk of accident!

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