94 850 Wagon Max Fan Relay Hot, 4 speed not working

850heat · Post by **850heat** » 25 Nov 2019, 18:32

Hello,

My 94 850 wagon (with the MCC) has always worked on blower fan speeds 1-3, but never worked well on fan speed 4. By pulling the max fan speed relay from behind the glovebox and putting it back in, I can get speed 4 back for a short while, but usually after a few minutes it will stop. I've recently noticed that the relay gets very hot after these few minutes, plug 87 is a bit charred. Please see pictures.

Is there an obvious reason why its doing this? I tried replacing the relay but it did not solve the problem. Is there an issue with the resistor?

Cheers

Post by **RickHaleParker** » 26 Nov 2019, 00:26

Speeds 1, 2, & 3 are controlled by the resistor pack. Speed 4 switches on the relay and connects the fan motor directly to the Battery.

Check the relay socket, what condition is it in?

Probably overheat and burn like the relay terminal. You pull the relay out and reinsert, you get a good connection until it burns up again.

: 2019-11-26 (3).png (257.51 KiB) Viewed 1122 times

Post by **BEJinFbk** » 26 Nov 2019, 01:03

Sounds like you need to replace both the relay and socket.
You may also have a worn blower motor issue that caused
your relay/socket problem. How old is that motor?

Post by **dcarlson12** » 08 Jul 2020, 19:22

Did you ever solve this problem? If so, ????

850heat · Post by **850heat** » 23 Nov 2020, 08:56

dcarlson12 wrote: ↑08 Jul 2020, 19:22 Did you ever solve this problem? If so, ????

I have not fixed it, have been doing OK with just three fan speeds.

I believe it is probably the bad socket/relay. The blower motor is very new, but I replaced an older one recently that was almost shot.