Removing and installing ABS control unit J104/ABS hydraulic unit N55, RHD vehicles — VW

Removing and installing
ABS control unit
J104
/
ABS hydraulic unit
N55
, RHD vehicles
Special tools and workshop equipment required
Torque wrench
V.A.G 1331
Torque wrench
V.A.G 1410
Brake pedal depressor
V.A.G 1869/2
Sealing plugs from
repair kit
1H0 698 311 A
The transport protection for the contact pins must always be placed on the hydraulic unit after the control unit has been disconnected from the hydraulic unit.
No warranty can be assumed for hydraulic units without transport protection.
1
Transport protection for contact pins (foam)
2
Sealing plug M10
3
Sealing plug M12
Removing
Location:
The control unit is bolted to the hydraulic unit and is located on left in the engine compartment.
1
Brake booster and brake master cylinder
2
Hydraulic unit and control unit
WARNING
Do not bend the brake lines in the area of the hydraulic unit!
Read out and note the existing control unit code.
Removing air filter housing:
Petrol engine
Rep. gr.
24
Air filter; Removing and installing air filter housing
Diesel engine
Rep. gr.
23
Air filter; Removing and installing air filter housing
Remove battery
Electrical system
Rep. gr.
27
Battery; Removing and installing battery
.
Remove battery tray
arrows
.
Apply
brake pedal depressor
V.A.G 1869/2
.
Connect hose of bleed bottle
1
to bleed valve of front left brake caliper.
Open bleed valve.
Connect hose of bleed bottle
1
to bleed valve of rear left brake caliper.
Open bleed valve.
Depress brake pedal at least 60 mm using
brake pedal actuator
V.A.G 1869/2
.
Close front left and rear left bleeder valves.
Do not remove
brake pedal depressor
V.A.G 1869/2
.
Place sufficient lint-free cloths under the control unit and hydraulic unit.
Ensure no brake fluid gets onto contacts.
First identify the two brake master cylinder brake lines
A
and
B
and unscrew from the hydraulic unit.
Immediately seal brake lines and threaded holes using sealing plugs from
repair kit
1H0 698 311 A
.
Identify brake lines (brake calipers)
1 to 4
, unscrew and seal.
Release connector in direction of
arrow 1
.
Disconnect connector in direction of
arrow 2
.
Unscrew bolt
3
from retainer.
Pull hydraulic unit together with control unit and retainer sideways out of rubber dampers of bracket.
Unbolt control unit from hydraulic unit
Chapter
Installing
Install in reverse order of removal, observing the following:
Note
Remove sealing plugs from new hydraulic unit only when the corresponding brake line is to be fitted.
If sealing plugs 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.
Before installing bracket of
ABS hydraulic unit
N55
into console, spray rubber dampers with
silicone lubricant
D 007 000 A2
.
WARNING
Ensure that rubber dampers of retainer are not pressed out of bracket when installing. After installing, check hydraulic unit with control unit for proper seating, otherwise malfunctions can occur.
Remove
brake pedal depressor
V.A.G 1869/2
.
Bleed brake system
Chapter
.
Coding
ABS control unit
J104
:
Vehicle diagnostic tester
.
To do this, basic setting of the
steering angle sender
G85
, the
lateral acceleration sender
G200
and the
brake pressure sender
G201
must be carried out.
Specified torques
Chapter
“
Assembly overview - control unit and hydraulic unit
”