Control Module, Separating From Hydraulic Unit

Replace the control module:

If the Vehicle Diagnostic Tester => has determined that the control module is faulty "Control Module Faulty".
If there is visible damage to the control module housing or to the connector.

CAUTION:

A control module that was removed cannot be attached to a different hydraulic unit.

ABS Control Module -J104- :

with integrated Brake Pressure Sensor 1 -G201-,

with integrated Transverse Acceleration Sensor -G200-,

with integrated Rotation Rate Sensor -- :G202 ,

with integrated Longitudinal Acceleration Sensor -G251-,

with integrated Electromechanical Parking Brake Control Module -- :J540 .

The components cannot be changed individually or removed.

-- 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 .

If the ABS Control Module -J104- is faulty, it can be replaced separately.

If the ABS Hydraulic Unit -N55- is faulty, it must be replaced together with the ABS Control Module -J104-.

Control Modules, Replacing:

CAUTION:

A control module that was removed cannot be attached to a different hydraulic unit.

NOTE:

Before removing the control module, read out the DTC memory and print out the error code if necessary.

The control module and the hydraulic unit can be separated.

The ABS Hydraulic Unit -N55- with the ABS Control Module -J104- must be removed in order to separate the control module and the hydraulic unit.

ABS Control Module -J104- WITH ABS Hydraulic Unit -N55-, REMOVING AND INSTALLING

The replacement should only be done by trained personnel with qualified technical training.

Only the new parts in the repair kit may be used.
Only new bolts may be used for attaching the control module to the hydraulic unit.
The seal on the control module must not be pulled out or raised up.
The seal on the control module cannot be replaced.
Blowing the control module or hydraulic unit out with compressed air is not permitted.
The valve coils inside the control module cannot be readjusted.
The valve coils inside the control module cannot be replaced.
The pressure sensor must not be changed or damaged.
The pressure sensor cannot be replaced.
The sensor housing must not be under any mechanical load.
No measurements may be performed on the contacts in the control module.
No measurements may be performed on the contacts in the hydraulic unit.
The valve bodies inside the hydraulic unit must not be damaged or bent.
The contacts cannot be replaced.
Using contact sprays on the contacts and pressure sensor are not permitted.
Make sure there are no foreign objects between the control module and the hydraulic unit.

Special tools and workshop equipment required

Torque Screwdriver:VAG1624 1-5 Nm with external TORX socket E6
ESD Work Surface:VAS6613

Procedure

CAUTION:

Only separate the ABS Control Module -J104- from the ABS Hydraulic Unit -N55- when they are removed.

-- Refer to ABS Control Module -J104- WITH ABS Hydraulic Unit -N55-, REMOVING AND INSTALLING

NOTE:

The :VAS6613 has sufficient grounding to protect against an electrostatic discharge.

-- Place the hydraulic unit with the control module on the :VAS6613 .

The control module -2- faces up and the hydraulic unit -4- with the pump motor and connector -3- faces down.

Fig 1: Identifying Hydraulic Unit
Courtesy of AUDI OF AMERICA, LLC

-- Remove the bolts -1- and dispose of them.

-- Carefully remove the control module upward holding it vertically.

NOTE:

Be careful not the hook the valve coils when removing them otherwise the valve coils could get stuck on the mount.

CAUTION:

There is a risk of destroying the hydraulic unit.

Cover the open hydraulic unit. Protect the hydraulic unit, the sealing surfaces, the valve bodies and the pressure sensor from dirt and getting damaged.
Do not use battery voltage to check the pump motor otherwise contact surfaces could get burned.
Protect the contact surfaces on the pressure sensor against mechanical damage and electrostatic discharge. The :VAS6613 grounds the technician sufficiently to protect against overcharging components.