S51 CLIMATE CONTROL SYSTEM NOISY' / (IN PASSENGER COMPARTMENT) - Alfa - 147 - eLearn

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

1	CHECKING ELECTRIC FAN	All OK	Problems met	Operation
		Results of the tests
	Check the climate control system fan In particular, ascertain: 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 fan Op. 5040C30
2	ACTIVE DIAGNOSIS WITH DIAGNOSTIC EQUIPMENT	All OK	Problems met	Operation
	Using diagnostic equipmen t (Examiner or other instruments), carry out active diagnosis of the fan at the different speeds (in climate control system control unit mode)	Continue to Step 3	Electric fan operation irregular	Replace fan Op. 5040C30
3	CHECKING DISTRIBUTOR DUCT	All OK	Problems met	Operation
	Check for the presence of foreign bodies and damaged parts inside the distributor duct assembly	Continue to Step 4	Presence of foreign bodies or damaged parts inside the duct distributor assembly	Overhaul the duct distributor assembly Op. 5040C10
4	CHECKING THE AIR DUCTS	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 5	Ducts obstructed or damaged	Repair the ducts and vents
5	CHECKING CORRECT OPERATION	All OK	Problems met	Operation
	Check that the fault is no longer present		Fault persists	Search for the fault starting from another symptom'