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

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Special tools and workshop equipment required

Vehicle Diagnostic Tester
Brake Pedal Actuator:VAG1869/2 .
Container from the Brake Charger/Bleeder Unit:VAS5234
Sealing plugs from Repair Kit:1H0 698 311 A

Transport protection for valve body (foam)
Sealing plugs M10
Sealing plugs M12

NOTE:

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 .

Removing

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-- Turn off the ignition.

-- Insert the :VAG1869/2 between the brake pedal and driver seat. Preload the brake pedal at least 60 mm.

NOTE:

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.

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-- Connect the container hose -2- as shown in the illustration.

WARNING:

Brake fluid is poisonous. NEVER siphon brake fluid with your mouth!
Wash off any brake fluid that comes into contact with the skin with a lot of water.
If brake fluid comes in contact with the eyes, wash out the eye(s) and see a doctor.
Refer to BRAKE FLUID GENERAL INFORMATION

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

-- Close the bleed screw and remove the container.

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

NOTE:

Do not remove the :VAG1869/2 .

-- Remove the tower brace. .

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

-- Mark the brake lines for installation later.

WARNING:

Brake fluid is poisonous. NEVER siphon brake fluid with your mouth!
Wash off any brake fluid that comes into contact with the skin with a lot of water.
If brake fluid comes in contact with the eyes, wash out the eye(s) and see a doctor.
Refer to BRAKE FLUID GENERAL INFORMATION

-- Remove all brake lines form the hydraulic unit -2-.

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CAUTION:

Danger of damaging the brake lines.

Do not bend the brake lines near the hydraulic unit.

-- Seal off the brake lines and threaded holes with the plugs from the Repair Kit:1H0 698 311 A .

-- Disconnect the connector -1- from the control module -3-.

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.

Clean a dirty connector housing thoroughly with compressed air.

-- Remove the hydraulic unit and control module from the bracket.

-- If required, remove the bracket from the hydraulic unit.

CAUTION:

There is a risk of destroying the hydraulic unit.

The pump motor may not be separated from the ABS Hydraulic Unit -N55-.

NOTE:

The ABS Control Module -J104- can be replaced separately. Refer to CONTROL MODULE, SEPARATING FROM HYDRAULIC UNIT .