The AC fan won't turn off!

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SuperK
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The AC fan won't turn off!

Post by SuperK »

I just installed AC on my DOHC recently... I have this wierd issue though.

If I run AC while driving the car, when I turn off the car, the AC fan stays on.

I have to turn the key just so the starter engages, and that turns off the AC fan.

However, if I forget, and go work all day, I am met with a nice dead battery, which means, the fan never turns off obviously.

Maybe i got some bad relays? Anyone have a suggestion on this?
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chrome730
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Re: The AC fan won't turn off!

Post by chrome730 »

thats actually happened to me before once or twice but it stopped. If you find out what it is, let me know so i can take care of it too.
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Re: The AC fan won't turn off!

Post by umcamara »

The normally open circuit of the condesnser fan relay receives constant power from the engine main fuse and trasfers it to the condenser fan motor when in the closed position (only happens when the A/C relay is in the closed position).

One of the only things that could be happening here is the condensor fan relay is somehow sticking in the closed postion, or the A/C fan relay is doing the same, causing the condensor fan relay switch to close and feed power to the condenser fan.

I've never seen these relays (since I don't have A/C), but they're likely standard automotive 30A/5-pole relays, replace both of them. This SHOULD solve your problem.

Report back with the results. (As I know you will whether we like it or not).
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SuperK
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Re: The AC fan won't turn off!

Post by SuperK »

Oh, right... I found the issue.

The ground wire on the relays was loose, so the connection wasn't stable. Oops :oops:
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Re: The AC fan won't turn off!

Post by beefmobile »

glad you found it
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