S80 1998 radiator fan

My radiator fan will not switch off and has run my battery down.
Ive disconnected the 60amp master fuse and re charged the battery.
Is there a faulty relay or sensor that might have caused my problem.
If so where are they?
There is no Haynes manuel for the S80.
Would the S70 manuel show similar wiring layouts as the S80
Thanks for any advice.
Chris

[Paul Wildsmith]

Doubt we'll ever see a Haynes manual for the S80. Wiring will be nothing like the S70. All cicuitary is control by a multiplexed system masterminded by a couple of computers and associated software.

Your problem may indeed be a simple thermostat - but could also be a software glitch. I've not looked, but if you can see a thermostat on the radiator somewhere it may be worth a look. Otherwsie a visit to your local Volvo dealer.

Paul Wildsmith
VOC S80 Register Keeper

Thanks Paul
Ill take your advice and have a nose under the bonnette
and then no doubt go to a Volvo dealer.
Its not a problem at the moment with the fuse removed but Sods law says Ill soon be stuck in a traffic jam with high temperature and no fan
Cheers
Chris

[Richard Swinney]

Chris,

Last summer I had the inverse of your problem on my T6 in that the fan would not cut in when the engine got hot.

It spent some time going back/forth to the dealer, and at the thrid attempt they fixed it under warranty with a replacement radiator fan assy from sweden.

IMHO the dealer appeared to be learning by trail and error on my car and one of the technicians admitted as much, which I found a bit frustrating.
No error codes were saved in the OBD system except the "stop engine" that occurred in my display when it overheated on the first attempt.

What I learned from this was that:

a) there are control relays in the engine bay and within the radiator fan assy although the dealer would not tell me which / where they were.
b) There is a water thermostat which talks/ sends to the ECU.
c) The ECU drives the temp guage on the dash and the fan assy.
d) The fan speed/ and on/off is affected when the aircon is switched on as the aircon rad needs a constant airflow to work when the car is crawling in traffic. ( my temporary fix was to keep the aircon on all the time by this was grim in the spring and heavy on fuel consumption)
e) The aircon system can start the fans at any time.
f) The aircon system starts the internal blower fan after about 30 mins since last driving car with aircon on to help remove condensing moisture from the system.

I don't know if any of this helps, but knowledge is power :-)
Especially with no prospect of there ever being a haynes manual.

Good luck with the diagnosis.

Richard

Thank Richard and all,
I am booked in to dealer in a couple of weeks time (Yes it does seem a long time !)
It seems there has been a common computer glitch on the S80 which may have caused my radiator problem. Apparently to do do with the self dimming mirror
My car computer is to have a chat with Sweden it seems, once the fascility has been set up.
Fingers crossed
Ill fill you all in later if you like
Chris UK

Hello

The radiator fan has been a common failure on the S80 (it is either on all the timr or does not work at all!)
This is due to a problem in the "fan control moduel".

To fix this problem it requires the replacement of the complete fan assembly however, this could be cheaper than it sounds.

Because volvo are aware of the problem they will pay 50% of the total cost (even if the vehicle is out of its 3 year warranty!!).

Ask your dealer to check the "claim types" for your vehicle.

**print this out and take to your dealer**

Regards Chris.

Thanks Chris
Thats really useful
Ive printed your reply and will give it a try
Chris (t'other one)

I am pleased that my local dealer has exchanged the radiator fan and control unit. I am so grateful with your help since he did not volunteer that Volvo pay 50% of the cost. It was only on production of your e-mail that it was admitted.
He must have been very confident in his workmanship since he had not replaced the fuse that Id removed to stop the fan.
All seems well now. Thank you for your advice
Chris

[sheerwater]

Good isnt it. Volvo sells a car which has a fault from new and they are good enough to pay 50% of replacement. I always thought that under the sale of goods act the product had to be fit for the purpose it was going to be used for and that really the ''warranty'' od however many years is irrelevant. cheers Nigel