My 2002's cooling fan is constantly on, even when the car is off. It just started yesterday while I was at work. It ran until my battery had nothing left to give. Any ideas that would cause this? Bad relay maybe?

Thanks!

 

Sounds like a sticking relay... I would check into that first...

 

Do you happen to know where the relay is. I don't have the repair manual, and I bought the car used and don't have the owner's manual either. Thanks in advance.

 

https://www.northamericanmotoring.co...t=fan+turn+car

 

Are you sure it's not the power steering pump? that is what happened to me. It does sound like a fan when it doesn't turn off.

https://www.northamericanmotoring.co...r+steering+fan

 

I sounds like it always does when you turn off the car. So I'm almost positive it's the cooling fan. I'll have to check it when I get home to be sure though. Also it's past the good ol' 50K mile mark so I'm going to have to pay for this repair myself.

 

I had a problem w/ a Mazda... exact same issue. Cooling fan stayed on after I turned the car off (and the engine didn't need additional cooling). It ran all night until the battery died.

It was a bad relay. The relay was fairly easy to replace and wasn't that expensive.

I took the car into the dealer and said "replace the cooling fan relay" and they said OK. An hour later, a grease-covered mechanic came out and said "Mr. Granger... I found your problem. You have a bad cooling fan relay!" I replied back, "N $hi+ Sherlock... I told you that an hour ago." and I had to track down the dealership manager to explain to the entire service department that 'replace the relay' does NOT equal 'go and diagnose a problem'.

Oh well...

If you have the Bentley guide, you can probably do this work yourself. It might not be the problem, but a new relay can't be THAT expensive and it just might save you hundreds in diagnostics and repair at a dealership or mechanic.

 

This happened to me on my '02 - there is a resistor pack that is part of the fan assembly that fails and causes the fan to run continuously. There is a power connector to the fan that you can disconnect when you stop the car until you get it fixed. It's just to the right of the radiator shroud and is oval shaped. I think it has 6 pins inside. If you disconnect it the fan will stop.

The repair requires the entire fan assembly to be replaced.

 

This diagram MIGHT help the discussion: http://www.realoem.com/bmw/showparts...20&hg=17&fg=05

 

It looks like the relay (part #9) is in the diagram, but it doesn't show exactly where it goes.

The diagram also provides you with the part numbers (for a MCS, I was just guessing) for the fan assembly pre and post 3/2003 assemblies.

Real OEM used to have the wholesale price listed... the must have pulled that... too bad! At least you can call your parts department and have a reasonable conversation on the phone with both of you looking at the same diagram.