After tightening, check:

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if all the bolts have made contact,
if the control module and hydraulic unit are touching all the way around.

-- Install the hydraulic unit. Refer to ABS Control Module -J104- /ABS Hydraulic Unit -N55-, REMOVING AND INSTALLING .

After replacing the control module and bleeding the brake system:

-- Select the "Replace" function for the ABS Control Module -J104- /ABS Hydraulic Unit -N55- using the Vehicle Diagnostic Tester in Guided Functions .

All the ESP warning lamps must go out.

WARNING:

Risk of accident!

Make sure the brakes are working correctly before driving the vehicle for the first time.