I was driving on the freeway last night and my a/c went out. It just completely stopped any air flow. It won't blow hot, or cold air at all. Does this sounds like a compressor problem??

 

No it's not the compressor, you have a problem with the interior fan. Probably the power transistor, but could also be the fan motor.

First test is to find the fan motor under the dash on the far right side of the car. It has a plug with two fairly thick wires. Turn the key on and set the fan switch to high. Measure the voltage between the two wires (motor still plugged in). If you have 12 volts but the motor doesn't run, the motor is bad. If it's zero volts, next measure from each wire to ground. If you have 12 volts on both wires the power transistor is probably bad (or a problem with the control panel). If you have zero volts on both wires the fuse (under the hood I think) is probably blown.

 

Mine is doing the same. Totally stopped. I pulled the fan it spins when connected to the battery. I have 12 volts at the fan plug with the fan setting off or on? What would effect this a relay? and where is it?
Help going through the desert this weekend and would like my fan to work...

 

One lead of the fan always has 12 volts. The other one is switched to ground by the power transistor to make the fan run. You need to measure between the two leads to see if the motor is being powered up. Also when a fan motor is nearly dead, it often becomes intermittent. It may work when taken out for a test but not when installed.

 

mk could it also be that it needs to be re-greased?

 

Generally on these little motors, the brushes wear out before the bearings give trouble. Officially the motor is non-serviceable, replace it as a unit.

 

The fan loads when connected spins for half second you hear the relay load and it quits.

I disconnect the alluminum finned sensor not sure what it is and the voltage goes away.

Reads about 1kohms.

Not sure you can connect the fan to the battery and it runs non-stop.

Also how would you measure the fan speed **** shouldn't there be a way to measure the ohm resistance increasing as you turn it down and up?

 

The aluminum finned thing is the power transistor, it's probably bad. Unplug the power transistor and jumper the two big wires in the plug. If the fan runs all the time then, replace power transistor.

The control panel has a computer in it and I think it applies pulses to the power transistor to vary the fan speed. It's not a simple resistor setup.

 

Thanks,

jumpering the power transistor leads awakened the fan!

I will break down and buy the transistor.

I will submit a final post to confirm it was the problem for future searchers with the same trouble.