A/C, defrost problem
Thread Starter
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
A/C, defrost problem
I'm having problems with not being able to use my defrost or heat. I have an '85 and there are two switches for the HVAC. Top one selects A/C, heat, defrost, etc. It works just fine. The bottom switch selects hot or cold. Its stuck on cold and will not move at all.
I tried disconnecting the battery, didnt work. I checked the fuses, all good. Could it be a wire or something thats come disconnected? I really need my heat before winter gets here. I'm already having trouble seeing at night due to the window fogging up.
I tried disconnecting the battery, didnt work. I checked the fuses, all good. Could it be a wire or something thats come disconnected? I really need my heat before winter gets here. I'm already having trouble seeing at night due to the window fogging up.
Thread Starter
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
Just took the unit out and couldnt see anything wrong with it. I've had this problem since a white plastic plug on the A/C system near the firewall popped off. I reconnected it and the temp select hasnt worked since.
ttt
ttt
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Temperature is controlled by a cable from the Dash Controls to the Heater Box. Sounds like yours is frozen or broken internally. You should have seen the connection when you removed the Panel. Follow it to the heater box (you'll probably need to remove the passenger side hush panel) and see if you can move the arm it's connected to on the heater box. If so, you need a new cable.
Drifting
Joined: Apr 2000
Posts: 1,879
Likes: 1
From: Lockport, IL Let's get em ALL home soon!
If you do have a manual select, the cable is connected to a threaded rod and the rod is connected to the blend door with the white plastic clip. Sounds like you have set the clip too far on the rod and now have no play in the cable for movement of the lever.
Thread Starter
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
I cant get the unit out of the dash, theres one bolt that wont come out. It just spins in the hole and yes I tried pulling on it with no luck. Dont wanna break the plastic trim.Yes its an '85 so its manual select, this stuff must be buried in the dash cause i'm having trouble finding it. So what I need to do is move the clip so that the lever moves freely? I got it. Thanks guys.
Drifting
Joined: Apr 2000
Posts: 1,879
Likes: 1
From: Lockport, IL Let's get em ALL home soon!
You might not have to remove the unit from the dash. The clip would be located by the blend door near the passenger side firewall. You should be able to get to it by removing the passengers hush panel under the dash and reaching up to it. When I did mine, I removed the passenger seat so I could lay flat on the floor and work. I also took the top dash pad off so the sun could shed some light behind the dash but that is just a personal preference.
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Thread Starter
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
I've removed the passenger side hush panel and have located 2 vacuum lines that go around the HVAC "black box". One is smaller and orange and goes into vacuum advance type thing near the door on the firewall. The other is black and goes underneath the black box, goes up the side, and then disappears on top of it. It has some unleggible writing on it. They both come from the center console area. I could use some help in finding the little clip because I dont really know much about HVAC systems. A picture would be helpful if anyone has one. Thanks.
Thread Starter
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
I found the problem. The lever was getting stuck on the bracket that holds the ECM inside the dash. I had to get into an akward position, now I see what you meant about removing the seat. I had trouble finding the clip and lever because I was looking for a white plastic clip, it was steel.
About a month ago I took the ECM out, so I must not have put it back in right or something. Thanks for the help.
About a month ago I took the ECM out, so I must not have put it back in right or something. Thanks for the help.
on a successful repair.
