S51 CLIMATE CONTROL SYSTEM NOISY' / (IN PASSENGER COMPARTMENT) - Alfa - 156 - eLearn

3233172 - S51 CLIMATE CONTROL SYSTEM NOISY' / (IN PASSENGER COMPARTMENT)

The climate control is working properly, but there is excessive noise coming from the distributor duct assembly

1	ELECTRIC FAN CHECK	All OK	Problems met	Operation
		Results of the tests
	Check the climate control fan and ensure the following in particular: there are no foreign bodies inside the fan casing there are no vibrations at the various speeds (causing operation with the fan switched off, but the electrical connection engaged)	Continue to Step 2	Fan dirty	Clean the fan casing and all the ducts
		Continue to Step 2	Electric motor noisy, fan unbalanced	Replace the electric fan Op. 5040C30
2	ACTIVE DIAGNOSIS WITH DIAGNOSTIC EQUIPMENT	All OK	Problems met	Operation
	Using the diagnostic equipment (Examiner or other instruments), carry out (in the climate control control unit ambient) the active diagnosis of the: electric fan at the different speeds mixture, distribution and recirculation motors	Continue to Step 3	Electric fan operation irregular	Replace the electric fan Op. 5040C30
			One of the motors operation is irregular	Replace one of the motors (see Assembly 5040D)
			Motor flap operation irregular	Replace the flap Op. 5040C24
			Presence of foreign bodies or damaged parts inside the duct distributor assembly	Overhaul the duct distributor assembly Op. 5040C24
3	AIR DUCTS CHECK	All OK	Problems met	Operation
	Check that the air ducts inside the dashboard and the vents are intact and that there are no foreign bodies which could cause noise	Continue to Step 4	Ducts obstructed or damaged	Restore the operation of the ducts and the vents (see Assembly 5010B)
4	CHECK 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'