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92stockbird
08-16-2013, 02:17 PM
Hey guys,

Last year when I drove my 92 sc the ac worked. In Jan. the ac/heater started blowing a small amount of air. In June, it quit altogether.
I checked fuses, including under hood, found some that were corroded, and replaced them. Still doesn't work. Last year, I thought I had seen a TSB for the ac, but if I had, it's gone. Does anyone know if there is a common problem with the ac/heater on these cars?
Thank you for any help you can give.

Jim

John 3:16

MadMikeyL
08-16-2013, 02:40 PM
When you say is was blowing a small amount of air, do you mean the fan only went on low speed, or do you mean it wasn't blowing cold? If it slowly started blowing warmer air, that is a classic symptom of the system leaking refrigerant. If it is just the fan doesn't blow fast, then first check the blower motor resistor, then the fan itself, and if both of those check out good, then if you have automatic climate control, the head unit may be bad.

92stockbird
08-16-2013, 11:04 PM
A very small amount of cold air was coming from the vents.
Not sure what the auto climate control is. Mine has the buttons, Max ac, norm ac, heat, vent, and to small slender switches that raise or lower the temp., and the slide switch.
If it is the head unit, is it possible to get a good used one?

Thank you,
Jim

John 3:16

MadMikeyL
08-17-2013, 07:56 AM
That is the manual control, and they never go bad.

When you say "A very small amount of cold air was coming from the vents" that is not clear. Was the air not as cold as it used to be, or did the fan not blow as fast as it used to?

92stockbird
08-17-2013, 12:55 PM
The air coming out of the vents was just as cold as before, it wasn't enough to cool the interior. In July the blower quit

dthompson
08-17-2013, 01:34 PM
is it me or does it sound like the blower motor is bad or the resistor? You can get either of those parts for about $20 at rockauto.com

to test the blower motor (per service manual)

use a 10ga wire and jumper the neg wire (black) on the blower to neg terminal on the battery. if the blower runs, then it is good and the problem is external to the blower.

to test the blower resistor:
check continuity of resistors. if the blower only operates on high, check the thermal limiter.

otherwise check the wiring between the selector switch and the motor for proper continuity.

hope it helps...
Derek

92stockbird
08-17-2013, 03:51 PM
What does the thermal limiter look like, and how do I check resistors?

dthompson
08-17-2013, 05:30 PM
It said do a continuity check on the resistors. I've not done it before. I have taken the resistor module out before, its right below the blower motor. I would remove it and inspect then check continuity across the resistor(s). I am not sure about the thermal limit, but since yours is blowing slow, I don't think that's the problem.

92stockbird
08-17-2013, 10:56 PM
I will try your recommendations after the rain stops. Hopefully we'll figure it out.
I'm thinking, since it stopped blowing, either the motor, or the resistor.

Mike Puckett
08-23-2013, 10:38 AM
If you need a new blower I've got a couple from 90's and a couple from 94's. One or the other should fit a 92.

S_Mazza
08-23-2013, 11:55 AM
It said do a continuity check on the resistors. I've not done it before. I have taken the resistor module out before, its right below the blower motor. I would remove it and inspect then check continuity across the resistor(s). I am not sure about the thermal limit, but since yours is blowing slow, I don't think that's the problem.

My resistor went bad and the fan stopped blowing. When I took it out, it was rusted to pieces. Pretty obvious what the problem was!