I have a 92 that the blower motor is not blowing. I have checked the fuse on firewall, it is fine, i hotwired the blower, it runs, I changed the module, still nothing..... Weird thing though I am getting no power to the fuse that says A/C on the pass side fuse panel. The compressor is coming on and cycling. What next?? Oh also I am getting 12v to the red wire that plugs into the module.

Thanks

 

Trust you verified that the blower and module ground is good. Sounds like you may not have power to the Programmer or it may not be functioning - Check the blower signal from the Programmer. It's the tan wire and it should have about 6 volts on it with the fan setting at "10"; 2.5 volts at "1", but the point is it should have voltage if the Programmer is sending the blower signal.

You probably checked the A/C Module (labled a/c mdl). That protects the circuit carrying actual blower voltage backed to the Programmer and it wouldn't have any voltage on it if the Blower isn't running. Look for a fuse that says A/C Prog. Also, if anything else is out - like the power seats or the cigarette lighter, suspect the Pwr Accessory Fuse - I'm pretty sure that provides battery power to the Programmer and a couple of other accessories and the fuse box that it's in is direct feed from the battery so you might want to check for some other stuff being out too.

Anyway verify the blower signal and that the Programmer is powered up. Unfortunately, the blower signal from the dash is on a serial data line and you really need a scanner to see if it's being sent to the Programmer. My guess is that if the Dash Controls are lit up, it's probably ok and if the Programmer has power but it isn't sending a blower signal, then it's dead, but that's only a guess.

 

OK, blower and module ground is good. The dash controls are powered up as far as the screen being illuminated and has temps and blower speed displayed. I am not sure of what you are talking of as far as the "programmer"? Where is it located? I am getting 0 volts at the module on the tan wire with the fan speed set to 10.

You stated checking the AC mdl, i am not sure where that is? Is that a fuse labeled that? The power acc fuse is good.

 

bump

 

For your Year, electronic a/c is pretty much controlled by the Programmer which to my knowledge is above and to the right of the accelerator, near the heater plenum. The vacuum harness for the air doors will be a part of the Programmer Assembly. It receives serial data from the dash controls and then sends low voltage signals to the Blower Module for blower speed control. Since the signal line (Tan) has zero volts, you need to ohm out that line between the Blower Module and the Programmer. You could also check the integrity of the Data Lines between the Dash and the Programmer - should be two; dark green - but unless you've taken the controls out or done something behind the dash, it would be rare for either line to be open or disconnected (and if they were, the a/c wouldn't work).

There are three voltage feeds to the Programmer: Battery Voltage for memory, a 5 amp fuse that is usually labled A/C Prog; Ignition Voltage which should be the 10 amp A/C Clutch fuse; and actual blower voltage which should be labled A/C MDL fuse and is also 5 amps. I don't know the location or the specific labeling of these fuses for your '92, but sometimes GM puts one or two in the dash location and another under the hood.

Just remember that the Programmer might not be the problem - it may not be receiving the blower signal from the Dash Control. The only way I know to troubleshoot it is with a Tech 1 or bi-directional scanner. With that, you can command blower speed and if it comes on, narrow the diagnosis to the control panel so you might want to consider a quick trip to a Dealer or an a/c shop with the right tools - Programmers and/or the Dash Controls can set you back a few bucks, though rebuilts might be available through the Last Detail - www.tld-corvette.com - for considerably less.