While driving last weekend with A/C on, my 2006 R53 made a weird noise. I have a Scan Guage II on my dash and realized my water temp was increasing. I pulled over and realized the low speed fan would not turn on - I only let it hit 228F so I didn't check the high speed. So I thought OK - it's the fan resistor failing (again). I drove the rest of the way home with my heater on high. The temp never got above 230F.

This weekend I replaced by previous fan (Dorman) with a new TYC from Rock Auto $66. The fan assembly did not have the unused wires for the early year cars so I am sure I have the correct fan.

Now, my fan will not turn on low speed when temps hit 221F. It only turns on when it hits 234F or when I turn on the A/C. The fan will run until it hits around 227F.

If I understand correctly, a bad resistor will prevent the fan from turning on with the A/C. Mine turns on fine with the A/C so it's not the resistor. Plus it's a brand new fan so I doubt it could be the resistor.

I checked both the Fan relays in the engine compartment fuse box and they test good. I checked the interior fuses as well.

Any thoughts, suggestions?

Thanks!

 

update: I did a little troubleshooting this evening. I pulled the light blue relay for the first stage fan speed and the fan came on at 221F. It turned off at around 214F. I also tested it with the A/C and it came on as it should. This is really strange...

I put the relay back in and the fan would not come back on at 221F. I tested the relay on my workbench with a 12V wall wart and DVM to check continuity and it tested fine.

So I'm currently running without the 1st stage fan relay in the car and it is doing what it is supposed to do.

 

is your power steering fan working? it's the one under the car. in the early models these are fused/relayed on the same circuit as the radiator fan, so a bad ps fan could prevent the radiator fan from kicking in low speed.

 

Great info for the OP (and others) here, minhi...

Unfortunately, this appears to be another of those frustrating posts that "die on the vine," ending up unresolved due to non-participation, and thus forum membership remains unenlightened as to the fixes for these types of gremlins.

 

So reviving this thread (sorry for letting it die!) - still same issue and yes, the power steering fan is working. I’ve just been turning the AC on so that the power steering fan kicks on and the radiator fan kicks on at 220F.

 

Thanks for the suggestions everyone.

 

Any resolution or updates to these problems?
Is everyone just doing a workaround. or did people actually fix the problem or find out the cause of the problem?