Continuously running cooling fan

silverrocket · Post by **silverrocket** » 28 Jul 2010, 20:03

Hello. I own a 1998 S70 with 130K miles. My cooling fan has just today started to run continuously, even when the engine is off. It runs until the battery is completely dead dead dead. At the moment, I have the fan simply disconnected from it's power source, temporarily eliminating the battery drain. My temp gauge is indicating nothing out of the ordinary. (horizontal at running temperature) The car is running nicely, as usual. The fan simply runs, and doesn't quit, ever. Thermostat seems like it would be effecting my temp gauge, so could it be the cooling fan relay? Has anyone ever had a similar problem? My check engine light is NOT on. Thanks.

Post by **jblackburn** » 28 Jul 2010, 20:17

Take the plastic end of a screwdriver and whack the relay a couple times.

If not, I believe that is the issue. If it were the ECT sensor, the fan SHOULD cut off at a maximum of 10 mins.

The relay constantly gets 12V, but it is supposed to need a signal from the ECU to turn on. If the contacts get stuck, however, it will keep the fan on.

silverrocket · Post by **silverrocket** » 28 Jul 2010, 22:39

Sure enough! I went out there and whacked it, but now the fan will not turn on at all. I think it's safe to say it's a bad relay. Thanks for the help.

silverrocket · Post by **silverrocket** » 29 Jul 2010, 11:57

I replaced the relay, and problem solved. Apparently part number 9442933 and 9442934 will both work. Just some reference for anyone looking here in the future. Thanks to jablackburn for the help. I love this site and I love my volvo!

flafusos · Post by **flafusos** » 04 Sep 2025, 10:55

silverrocket wrote: ↑29 Jul 2010, 11:57 I replaced the relay, and problem solved. Apparently part number 9442933 and 9442934 will both work. Just some reference for anyone looking here in the future. Thanks to jablackburn for the help. I love this site and I love my volvo!

Thanks mate, im one of the "anyone",really appreciate!