climate control help - Toyota Nation Forum : Toyota Car and Truck Forums

wambus · 06-24-2009, 08:24 AM

I have not posted in a while. I drive an 86.5 Supra (daily driver), N.A., manual. I have been focused on the suspension as most of the bushings were toast. I have most of that under control. Now I would like to address the climate control. The AC does not work and the fan does not appear to work in the low position. I just discovered that the compressor is not even turning on - what should I look for? Are there issues associated with the electronics that I can easily address? Is there a safety that prevents the compressor from running if it is low on freon? It sure would be nice to be able to cool off on my way home from work....

SupraTuned · 06-24-2009, 10:30 AM

Well man, unfortunantly, you will probably have to replace your blower motor, which isnt that difficult. You can buy the motor from autozone for about 30 bucks and then swap your fan onto it. As for the A?C, the chemical is probably worn out. Check the fuses, check the switch wire to the ac unit, and make sure the belt is not slippping.

Jeeves · 06-24-2009, 11:04 AM

If the other fan speeds work then it is not the blower motor. There ia a resistor pack that is accessible in the passenger foot well that needs to be replaced.

Here are two links for you to check out: #1 - Good Ole SOGI Tech Tip and #2 - Blower Motor & Resistor Repair Writeup.

wambus · 06-24-2009, 02:43 PM

I repaired one of those in a Datsun Pickup once. Thanks for the heads up on the location.

The reason I ask about the AC is that a friend of mine has an '89 Crown Vic County Squire wagon with a malfunctioning AC. It works sometimes but not others. He wired in a toggle switch and now it works all the time. I wondered if that was something I should look for here since the compressor does not turn on. I will check the fuses and such, although I think I have already checked them...

Jeeves · 06-24-2009, 05:53 PM

[img]http://xd.**********s.com/uploads/484204c681.gif[/img]

Based on this diagram, there is a pressure switch in the loop. Looks like (since it comes off the A/C Magnet Clutch Relay), it won't pull in without that pressure switch being triggered. So, my guess is that if there's not enough pressure/freon in the line it won't pull in the compressor to prevent damage from occuring.

ddouglas77 · 06-27-2009, 08:55 PM

Most cars have a high and a low switch to prevent the compressor from coming on. The only sane thing to do is to hook up A/C lines to your car and read the settings. If all is good, a sensor is out, if not, you have a low or high failure.

wambus · 07-06-2009, 09:55 AM

So, the bottom line is that it is not likely to be an issue with the control unit itself.....

Thanks for all of the input.