Connect the diagnostic equipment (Examiner or other instruments) to the diagnostic socket

• Check that there are no faults in the ABS control unit.

Move onto step 2

• Continue according to the instructions for the diagnostic equipment

End of diagnosis

Restore:

• the connection between the ABS control unit and the diagnostic connector
• the supply for the ABS control unit (Wiring diagram E7020 ABS ).

End of diagnosis

Using the diagnostic equipment (Examiner or other instruments) carry out the active diagnosis of:

• pump motor;
• solenoids

Move onto step 3

• Replace electrohydraulic unit-electronic control unitOp. 3340A12

End of diagnosis

Check that there are no leaks through the brake servo check valve

Move onto step 4

• Clean the check valve if it is clogged or dirty, or replace

End of diagnosis

Check the condition of the vacuum pipe and connectors and bands

Move onto step 5

• Renew the fixings or replace the faulty components

End of diagnosis

• Replace the vacuum pipe

End of diagnosis

Check the condition of the brake servo vacuum valveSee Test 3330DA Efficiency test of air pump and vacuum circuit for servo brake

Check the condition of the vacuum pipe and connectors and bands

Move onto step 5

• Replace the brake servo vacuum pumpOp. 3330D30

End of diagnosis

• Repair fastenings or replace the vacuum pipe

End of diagnosis

Check that brake servo is working properly:

Move onto step 6

• Replace the servo unitOp. 3330D10

End of diagnosis

Check the condition of the brake caliper pistons

Move onto step 7

• Replace brake calipersOp. 3310A30

End of diagnosis

• Replace brake calipersOp. 3310B36

End of diagnosis

Check that the fault is no longer present

End of diagnosis

Incorrect selection of diagnostic procedure