HVAC control unit problem?
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Joined: Dec 2006
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From: Elmhurst, IL
HVAC control unit problem?
So, I finally decided it was time to tackle my dead hvac blower fan problem on my 82 5 speed. I followed the troubleshooting guide in Wally's World on 928gt.com.
I fed the fan straight power off a battery, and it fired right up.
Of course, I checked the fuse, it is fine.
The relay is new, but I tried it in the with the horn to verify it is good, and it is. I then tried placing a jumper between terminals 30 and 87 on the relay, the fan kicked right on.
So, control unit?
What is the next step?
I guess I should mention that nothing about the control unit seems to work, for instance it does not light up.
You know how much I love getting help. Thanks in advance.
I fed the fan straight power off a battery, and it fired right up.
Of course, I checked the fuse, it is fine.
The relay is new, but I tried it in the with the horn to verify it is good, and it is. I then tried placing a jumper between terminals 30 and 87 on the relay, the fan kicked right on.
So, control unit?
What is the next step?
I guess I should mention that nothing about the control unit seems to work, for instance it does not light up.
You know how much I love getting help. Thanks in advance.
Last edited by robot808; Aug 25, 2007 at 11:36 AM.
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From: The Long Island
What I did was look around to see who had a parts car. Look on line for auto wreckers or have a local guy go out on their system for one. The cost is a lot less then you would think. I paid 100$ for mine from a guy in Virginia. Sorry, can't remember the place, was some years ago. If you get one cheap enough, just install and see what happens. Also, did you pull the old one out a check all connections. Maybe a cleaning of connections may help. Is there power to the control unit?
Chronic Tool Dropper
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The fan motor connects to the control head on the left side of the control head, near the front face of the controller (towards rear of car...). You can sometimes get access to that connector by removing the left side carpet cover on the console. If it's loose, the fan won't get power. More towards the rear edge of the controller on the same side is an edge connector that carries all the non-fan signals to the head. This one is sometimes dislodged when doing other work in the console, like maybe replacing the stereo head unit. This one is definitely accessible from the side panel area. Try this before you spring for another controller. The fan switch is the one industrial-strength part in the controller; the rest of the pieces are hobby-grade unfortunately.
Thread Starter
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Joined: Dec 2006
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From: Elmhurst, IL
Thanks guys, will definetly check those things. Is there a way to check the circuit by circumventing the head unit. Does anyone know which wires are the hot and ground going to and from the head unit? I would like to make sure that power is even getting there.
Thanks so much.
Thanks so much.
