2000 BMW 318 coolant and radiator fan

DOUG12121212

MEMBER
2000 BMW 318
4 CYL
2WD
MANUAL
70,000 MILES

Your Question

Radiator fan stays on all the time? I ran out of coolant a couple of weeks ago, so topped it up and it ran out after 300 miles I filled it again being told u haveto bleed iti have now done this and it ran out again. But this time the radiator fan has stayed on even with key out the fan stays on. The temperature gauge is at a normal level wen itr's hotit's hot and in the morning it's cold. Now the fan is always on until the battery goes flat so I have to dis-connect the radiator fan plug? The oil is clean and no white on the dip stick or oil filler cap so I do not think it is head gasket? I have sat for hours looking for leaks when running and when not but cannot find any.

where is my coolant going and how can I stop the fan?

1 Reply

DOCHAGERTY

MECHANIC
9,601 POSTS

The fan is controlled by a module that is built into the fan unit, it is called a final stage unit. Replacement of the entire unit is called for since the final stage unit is not available separately. The cooling system needs to be pressure tested overnight to determine where the coolant is going, it may not present itself when hot at an idle. It may also be the pressure cap, keep in mind that these are my best guesses, do not think that I can see the issue like you can, perform the overnight pressure test first, then we can proceed. Realoem. Com is an excellent site for exploded views of the cooling system and the fan, it will also give you retail pricing. Autobahn dismantlers in El Cajon Ca. (619)444-2290 is an excellent source for used BMW parts, call John and tell him I sent you.