Hello,
The electric radiator fan in my 2000 s80 won't stop, even after you power off the vehicle it just runs until the battery is dead. The dealer didn't even look at it and ordered a new radiator fan assembly but I'm suspicious that it isn't the problem, anybody have a good idea of what controls this fan that could be causing it to stay on like that even after the car is turned off and the key is removed?
Tom

This is a well documented problem with the S-80. There is an electronic fan control unit screwed in to the fan shroud near the motor. It controls the fan via input from the ecu. They have been dropping like flys. There are 2 failures. They either fail to start the fan, resulting in loss of A/C and overheating, or the won't shut off, resulting in dead battery. The controller is hard wired to the fan motor, and not available as a spare part, therefor the complete fan assembly is replaced with a redesigned unit.

Wow thanks for the info, I was wondering why the dealer just ordered a fan unit after hearing the problem without even looking at it... So there is no way to fix the existing controller, IE does anyone know what's actually wrong with it, electronically, that it could be fixed? The reason is that it's out of warranty now and apparently that fan unit is QUITE expensive!
Tom

I had the controller go out on my 2000 S80 T6. It would just pulse on and off, mostly off, and the engine would continually overheat and I would lose A/C. The fan assembly was replaced (under warranty), and it's never overheated again, and the A/C works fine now.

The new fan will run for 5-10 minutes after the car is stopped if I've been driving hard in the heat, but it'll go off.

Sounds like the controller. Your best bet is to replace the entire assembly, as the controller is not available separately. It's expensive, but it's the only way. The new ones are 'new and improved', and have completely different-looking controller boxes and fans, and the wiring is different. My dealer had it installed in a few hours.

Nobody has any ideas?