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1994 Climate controls works for 30 seconds then is unresponsive.
When you first turn the key on all controls work fine, fan up/down, change heater high/low. After about 15-30 seconds the fan slows way down and none of the buttons on the climate control work any more. Turn the key on and off and it works fine again for 15-30 seconds.
Change the
Corvette Heater Air AC Motor Blower Control Module 16173860
Did the connector bypass on the
AC/Heater Climate Control Programmer
I dunno what else to do!!! Getting under that dash was a nightmare!
Assume it's electronic HVAC controller, do the displays change when you push buttons after the system turns off?
No they dont change, its like frozen, the numbers do not change when speed up/down etc... It's frozen until you turn the key off and on. There is no error code either by holding the buttons.
When you first turn the key on all controls work fine, fan up/down, change heater high/low. After about 15-30 seconds the fan slows way down and none of the buttons on the climate control work any more. Turn the key on and off and it works fine again for 15-30 seconds.
Change the
Corvette Heater Air AC Motor Blower Control Module 16173860
Did the connector bypass on the
AC/Heater Climate Control Programmer
I dunno what else to do!!! Getting under that dash was a nightmare!
Explain exactly what you did in plain English.
Do you have any dashes across the screen on the control head?
I suspect the capacitors in the programmer is the problem and here is the link for the information. But before you go off into left field explain my request.
In plain English?
There is no dashes, the display freezes at whatever temp is on there and nothing can change it besides turning the car off and on.
Bypassed the vacuum hose connector by buying 7/64 vacuum tubing and connected them to the programmer directly.
I was told by a corvette mechanic that this would be the first step to try. I couldn't see how it would freeze up the climate control but I did it anyways. I figured maybe the vacuum wasn't strong enough to close/open switches or whatever that programmer does.
Last edited by NitroViper; 10-07-2018 at 03:02 PM.
Your mechanic was wrong. Which sucks, because you wasted time and cut up a perfectly good vacuum harness. If you still have the vacuum port that you bypassed, I'd be interested in buying it.
Your programmer is more than likely the culprit with a dying capacitor. The good news is, you know how to remove the programmer.
As said, the vacuum hoses have nothing to do with the electronics or displays. It does not even make sense and not even a good guess…….sorry.
The set up is fuse 43 gives power to the programmer and is hot all the time. Fuse 18 is switched on by the key which powers up the control head which then supplies data and a shared voltage. Cycling power with fuse 18 might bring it back but since it affects both units it would be hard to draw a definite conclusion. You might try it though just for additional data information.
Without having one or the other spare boxes it will be difficult to point a definite finger. It might be worth a shot replacing those 4 capacitors I have indicated in the programmer with the link I have furnished.
I can't remember anyone repairing the control head. Basically there's a display driver chip and I think another large IC. Been in there many times just can't remember exactly what's in there but there is not much at least in the way of replaceable parts.
I looked up the capacitors you mentioned and seem to find multiple versions with different specifications. I dont have the car where I am at now so I cannot check the numbers on these capacitors.
Do you have stock numbers? Manufacture part numbers?
All capacitors were 50 volt. Let the seller figure out what their stock number is. In a pinch I'm sure 35 volt would work OK since there are 12 or less volts on the caps. Just shop for those values at 50vdv starting off.
Look at the caps in my link, you can get an idea, about 1/2 inch.
10-06-2018, 03:45 PM
1994 Climate controls works for 30 seconds then is unresponsive.
