Removing and installing ABS control unit J104 and ABS hydraulic unit N55 — AUDI

🧭 Before you start

Fits: VW Caddy III (2K, 2004–2015); platform code 2C0

• Opens: brake fluid

Don't miss

• Do not bend the brake lines in the area of the hydraulic unit! — Read out and note the existing control unit code.
• Release particulate filter (do not remove) 26Emission control; Removing and installing particulate filter.
• Do not remove brake pedal depressorV.A.G 1869/2.
• No brake fluid must get onto the contacts.
• Before installing bracket of ABS hydraulic unit N55 into console, spray rubber dampers with silicone lubricantD 007 000 A2.

📋 Procedure

1. ⚠ Do not bend the brake lines in the area of the hydraulic unit! — Read out and note the existing control unit code.
2. Note or request radio code on vehicles with coded radio if necessary.
3. Disconnect battery Electrical system27Battery; Disconnecting and reconnecting battery.
4. Remove pressure pipe and intake connecting pipe together with regulating flap control unit 24Intake manifold; Removing and installing regulating flap control unit J808.
5. Remove charge air hose 21Charge air system; Assembly overview - charge air hose connections.

6. Clamp off hose from coolant expansion tank and pull it off.
7. Unclip fuel hoses and coolant hoses from charge air pipe.
8. Remove bolt (1).
9. Release retaining clips (arrows).
10. Remove charge air pipe together with connecting hoses between charge air cooler and intake manifold flap motor V157.
11. Remove intake manifold flap motor V15723Intake manifold; Removing and installing intake manifold flap motor V157.
12. Remove connecting pipe together with connecting hoses between charge air cooler and turbocharger 21Charge air system; Assembly overview - charge air hose connections.
13. Remove intake connecting pipe 23Intake manifold; Assembly overview - intake manifold.
14. Remove centre plenum chamber bulkhead General body repairs, exterior50Plenum chamber bulkhead; Removing and installing plenum chamber bulkhead.
15. Remove connecting pipe between intake hose and turbocharger.
16. Remove toothed belt guard upper part.
17. Release particulate filter (do not remove) 26Emission control; Removing and installing particulate filter.
18. Disconnect connector of exhaust gas pressure sensor 1G450(1).
19. Remove bolt (2).
20. Remove bracket (3) together with exhaust gas pressure sensor 1G450, and lay it aside.
21. Remove nuts (4).
22. Remove heat shield (5) upwards.
23. Unscrew nut (2).
24. Remove cover for brake lines (1).
25. Release connector in direction of (arrow 1).
26. Release connector in direction of (arrow 2).
27. Apply brake pedal depressorV.A.G 1869/2.
28. Connect bleeder bottle hose to front left brake caliper bleeder valve and rear left brake caliper bleeder valve and open bleeder valves.
29. Depress brake pedal at least 60 mm using brake pedal depressorV.A.G 1869/2.
30. Close front left and rear left bleeder valve.
31. Do not remove brake pedal depressorV.A.G 1869/2.
32. Place sufficient lint-free cloths under the control unit and hydraulic unit. [Note: No brake fluid must get onto the contacts.]
33. First identify the two brake master cylinder brake lines (A and B) and unscrew from the hydraulic unit.
34. Immediately seal brake lines and threaded holes with sealing plugs1H0 698 311 A.
35. Identify brake lines (brake calipers) (1 to 4), unscrew and seal.
36. Turn hexagon fitted bolt out of retainer.
37. Pull off ABS hydraulic unit N55 with ABS control unit J104 and retainer sideways from damper rubbers of bracket and turn upside down.
38. Unbolt retainer from ABS hydraulic unit N55 in engine compartment and remove.
39. Remove ABS hydraulic unit N55 with ABS control unit J104 upwards out of dampers. [Note: Do not remove sealing plugs1H0 698 311 A from the new hydraulic unit until the respective brake lines are about to be installed.If the sealing plugs1H0 698 311 A are removed too early from the hydraulic unit, brake fluid can escape, and it can then no longer be guaranteed that the unit can be sufficiently filled and bled.When installing, ensure that rubber dampers are not pressed out of bracket.]
40. Before installing bracket of ABS hydraulic unit N55 into console, spray rubber dampers with silicone lubricantD 007 000 A2.
41. Using assembly toolV.A.G 1410/8, carefully fit brake lines.
42. Tighten brake lines using special tool assembly.
43. Remove brake pedal depressorV.A.G 1869/2.
44. Bleed brake system .
45. Code radio.
46. Code ABS control unit J104 using .

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