AC Stays On When Switch is Off

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Apr 20, 2009 | 09:35 PM

bucket

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AC Stays On When Switch is Off

On my '69 350/350 vette, I can switch the ac off using the ac control, however, the ac stays on. Is the problem likely the ac selector control switch or something else?

If the selector control switch in the off position doesn't turn the ac off, should I just remove the ac fuse to shut the ac off as a temporary fix?

Apr 20, 2009 | 10:24 PM

Kevin_73

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From: Standing still with all my might Texas

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St. Jude Donor '09-'11

Quote:

Originally Posted by bucket

Does it do it at lower fan speed settings, or only with the fan on the high setting?

Mine does the same thing but only with the fan set to the highest speed.
The high blower relay is overheating and the contacts inside are getting stuck together. A new quality high blower relay would fix it, but I can't seem to remember to order one. I will just continue to use only the lower fan speeds only until I can remember to order a new relay.

Apr 20, 2009 | 10:28 PM

TimAT

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The blower fan stays on? Relay like Kevin says. If the a/c clutch stays on then you have a problem with the wiring somewhere.

Apr 20, 2009 | 11:36 PM

7T1vette

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From: Crossville TN

Bad switch or bad relay. Check them out individually with an ohmmeter to see if the contacts are correctly opening and closing [or if they are permanently stuck together].

Apr 21, 2009 | 02:38 PM

1hotrod

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This happened to me a couple of months ago.

One of the relay wires for the blower falls out, and grounds itself out by touching the other wires on the relay.

It's kind of hard to see, because the relay wires are facing down, but look around that area and make sure the contacts aren't loose.

Apr 25, 2009 | 12:03 PM

bucket

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It appears to be happening when the fan is set at a high speed.

Jun 4, 2009 | 10:06 AM

bucket

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Quote:

Originally Posted by 1hotrod

It has taken me some time to get back to this. Here is my question: Can you or somebody tell me exactly where I should look? Should I look at the switch inside the car, or somewhere under the hood of the car? If under the hood, exactly where?

Thanks

Jun 4, 2009 | 11:57 AM

CCrane65

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From: Wichita KS

Quote:

Originally Posted by bucket

The high speed blower relay is mounted to the front of the A/C housing in the engine compartment on the passenger side. It has 4 wires on it, one orange, one black, one purple and one blue. It (the relay cover) may be painted black. It is held with 2 screws into the housing and the wires hang down from it.

cc

Last edited by CCrane65; Jun 4, 2009 at 05:42 PM.