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

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-- Insert the : VAG1869/2  between the brake pedal and driver seat. Preload the brake pedal at least 60 mm. (By doing this, the valves in the brake master cylinder are closed and the brake fluid reservoir does not run empty.)

-- Remove the protective cap -3- from the bleed screw -1- on the left front caliper.

Fig 1: Identifying Protective Cap, Bleed Screw And Container Bleeder Hose

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-- Connect the bleeder bottle hose -2-.

-- Open the bleed screw to reduce the pressure in the brake system.

-- Close the bleed screw and remove the bleeder bottle.

-- Repeat the procedure on the left rear brake caliper.

• Do not remove the : VAG1869/2  .

-- Remove the engine cover. Refer to ENGINE COVER, REMOVING AND INSTALLING .

Vehicle with TDI Engine: 

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-- Remove the front exhaust pipe. Refer to the appropriate Service Information .

-- Remove the bolts -1- for the pendulum support.

Heat shield with Catch: 

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Not all models have the heat shield. 

-- Release the retainer -arrow-, pull the heat shield -1- off to the left and remove it.

Heat shield with Threaded Connection: 

Fig 2: Heat Shield - Threaded Version

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Not all models have the heat shield.

-- Remove the nut -1- and remove the bracket with the lock washer -3-.

-- Remove the heat shield -2-.

Continuation for All Vehicles: 

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-- Unclip the wiring guide.

-- Press the locking mechanism downward -arrow A-.

-- Release the connector -arrow B-.

-- Remove the connector -1-.

• Make sure that no brake fluid enters the control module connector housing. This could lead to contact corrosion and thereby cause the system to fail.
• A contaminated housing must be carefully cleaned with compressed air.

-- To protect against escaping brake fluid, place enough lint-free cloths in the area below the hydraulic control unit.

-- Mark the brake lines on the hydraulic control module.

Fig 3: Brake Line Tightening Sequence

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-- Remove the union bolts for the brake lines in the sequence -6 through 1- and push the brake lines slightly to the side.

-- Seal brake lines and threaded holes with clean sealing plugs.

Vehicles with High-Voltage System: 

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-- Remove the clip -1- and push the heat shield slightly forward.

-- Remove the union bolts -arrows- for the brake lines.

-- Free up the brake lines at the plenum chamber bulkhead and push them aside.

Continuation for All Vehicles: 

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-- Pull the hydraulic control unit -1- upward -arrow- and remove it.

-- Should the hydraulic control module be replaced, remove the bolts -arrows- and remove the mounting bracket -1-.

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