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

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850heat
Posts: 11
Joined: 25 Nov 2019, 18:14
Year and Model: 1994 850
Location: USA

Post by 850heat »

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

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RickHaleParker
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Post by RickHaleParker »

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.
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BEJinFbk
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Post by BEJinFbk »

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?
'98 V70 R - Well Equipped for Life Up North... ;)

dcarlson12
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Post by dcarlson12 »

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

850heat
Posts: 11
Joined: 25 Nov 2019, 18:14
Year and Model: 1994 850
Location: USA

Post by 850heat »

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.

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