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Home >> Audi >> 2017 >> S5 2D Convertible >> Repair and Diagnosis (Single Page) >> Brakes >> Brakes Control Systems >> Antilock Brake System (Cabriolet) >> 45 Antilock Brake System >> Control Module And Hydraulic Unit >> Abs Control Module -J104- /Abs Hydraulic Unit -N55-, Removing And Installing >> Removing
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Abs Control Module -J104- /Abs Hydraulic Unit -N55-, Removing And Installing: Removing

-- Read the control module version and make a note of it.

Use the Vehicle Diagnostic Tester to do so.

-- Disconnect the battery while noting the radio code. Refer to BATTERY, DISCONNECTING AND CONNECTING .

-- Insert the Brake Pedal Actuator :VAG1869/2  between the brake pedal and driver seat by pressing the brake pedal down at least 60 mm.

Fig 1: Brake Pedal Depressor VAG 1869/2 Inserted Between Brake Pedal And Driver's Seat
GWWA44-0020Courtesy of AUDI OF AMERICA, LLC

-- Connect the hose from a bleeder bottle to the bleeder screw on the left front caliper.

-- Open the bleeder screws on the left front and rear brake calipers to reduce the pressure in the ABS hydraulic unit N55.

-- Close the left front and left rear bleeder screws.

NOTE:

Do not remove the Brake Pedal Actuator :VAG1869/2  .

-- Press the securing clip on the connector to the control module -1- up.

Fig 2: Identifying Brake Lines
GWWA45-10016Courtesy of AUDI OF AMERICA, LLC

-- Pull the securing bracket in the direction of the -arrow- and remove the connector.

Fig 3: Pushing Retaining Plate And Disconnecting Connector
GWWA45-10017Courtesy of AUDI OF AMERICA, LLC
NOTE:

Make sure that no brake fluid enters control module connector housing. This could lead to corrosion of the contacts and thereby cause the system to fail.

A contaminated connector housing must be carefully cleaned with compressed air.

-- To protect against escaping brake fluid, place a lint-free cloth in the area under the control module J104 and hydraulic unit N55.

-- Mark the brake lines for installation later.

WARNING:

Do Not Bend Or Kink The Brake Lines.

-- Remove the brake lines from the ABS hydraulic unit N55 and brake master cylinder.

-- Remove the remaining brake lines -arrows- from the ABS hydraulic unit N55.

Fig 4: Identifying Brake Lines
GWWA45-10016Courtesy of AUDI OF AMERICA, LLC

-- Seal brake lines and threaded holes with plugs from repair kit.

-- Carefully remove the ABS hydraulic unit N55 together with the ABS control module J104 upward from the bracket.

When removing the ESP control unit from the bracket, make sure the rubber buffers do not fall into the engine compartment.

WARNING:

Strong vibrations (for example falls, impacts) can destroy the control module. Control module must then no longer be used.

-- Set the hydraulic unit N55 with the control module J104 down on a clean, level surface.

Seal the threaded holes and brake lines with plugs after removing the ABS control module J104 and ABS hydraulic unit N55.

WARNING:

The Hydraulic Pump Must Not Be Separated From The Hydraulic Unit N55.