F20 ABS WORKING IRREGULARLY - Alfa - 166 - eLearn

3308629 - F20 ABS WORKING IRREGULARLY

When the brakes are operated vigorously, the ABS system does not work properly, and so one or more wheels lock(s).

1	CHECKING WITH DIAGNOSTIC EQUIPMENT	All OK	Problems met	Operation
		Results of the tests
	Connect diagnostic equipment (Examiner or other instruments) to the diagnostic socket. Verify: that there are no faults in the ABS control unit the plausibility of all the parameters	Continue to Step 2	An error is detected in the control unit	Continue following the instructions for the diagnostic equipment
		Continue to Step 2	Lack of dialogue with the control unit	Restore the connection between the ABS control unit and the diagnostic connector ( See E7020 ABS )
2	ACTIVE DIAGNOSIS WITH DIAGNOSTIC EQUIPMENT	All OK	Problems met	Operation
	Using the diagnostic equipment (Examiner or other iinstruments) carry out the active diagnosis of: pump motor solenoid valves	Continue to Step 3	Pump and/or solenoids faulty	Replace electrohydraulic unit-electronic control unit Op. 3340A12
3	CHECKING BRAKE CALIPERS	All OK	Problems met	Operation
	Check that the brake caliper pistons run freely	Continue to Step 4	Front caliper pistons seized	Replace front brake calipers Op. 3310A30
	Check that the brake caliper pistons run freely	Continue to Step 4	Rear caliper pistons seized	Replace rear brake calipers Op. 3310B36
4	CHECK BRAKE PIPES/HOSES AND BLEEDING	All OK	Problems met	Operation
	Visually check that there are no kinks or restrictions in the brake pipes, bleed the system and check that fluid emerges from the bleed screws as normal	Continue to Step 5	There are kinks or restrictions, fluid does not come out normally	Replace the faulty section of pipe
5	HECK ON CORRECT OPERATION	All OK	Problems met	Operation
	Check that the fault is no longer present	End of diagnosis	Fault persists	Search for the fault starting from another symptom'