Control Module, Separating From Hydraulic Unit

Control Modules, Replacing

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.

If the control module is faulty, then the control module is to be separated from the hydraulic unit and only the control module replaced.
If the hydraulic unit is faulty, the hydraulic unit and the control module are to be replaced together.

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.

Replacing the control module 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

Electro-Static Discharge Work Surface: VAS6613

Fig 1: ESD Work Surface
Courtesy of AUDI OF AMERICA, LLC
Torx^® insert T25

CAUTION:

There is a risk of destroying the hydraulic unit.

The return flow pump must not be separated from the hydraulic unit.
The circuit board is laid open on a disconnected control module.
No moisture or dirt particles must get into the control module.
Avoid electrostatic charge.

Procedure

-- Remove the ABS Control Module -J104- /ABS Hydraulic Unit -N55-. Refer to ABS Control Module -J104- /ABS Hydraulic Unit -N55-, REMOVING AND INSTALLING, VEHICLES WITH GASOLINE ENGINE WITHOUT HIGH-VOLTAGE SYSTEM .

-- Touch a grounded object before working on electrical equipment ESD Work Surface: VAS6613 . Do not touch the connector terminals or electronic components directly.

-- Position the hydraulic unit with the control module on the ESD Work Surface: VAS6613 .

-- Remove the three Torx^® bolts -arrows- for the control module and dispose of them immediately.

Courtesy of AUDI OF AMERICA, LLC

-- Position the hydraulic unit with the control module from upward on the ESD Work Surface: VAS6613 .

-- Pull the control module off from hydraulic unit without tilting.

Fig 2: Control Module Pulled Off From Hydraulic Unit Without Angling

Courtesy of AUDI OF AMERICA, LLC

-- Cover control module solenoid coils with a lint-free cloth.

-- Check the cleanliness of the hydraulic unit sealing surface, if necessary clean with mineral spirits and a lint-free cloth.

CAUTION:

Protect the contact surfaces on the pressure sensor against mechanical damage and electrostatic discharge. The ESD Work Surface: VAS6613 grounds the technician sufficiently to protect against overcharging components.