A/C Fan Quit, Argh!

AC fan? Do you mean the additional fan on your 82? It's operated by the thermostatic switch in the pass. side head and ac switch. If the connector is off it will not run as the switched ground bypass is in the connector and with it disconnected it won't work. To test it if the connector is connected, pull it off and short the wire to ground (that's what the switch does), the fan should start running. If not, check for 12V power, if you have it, the motor is dead.
 
Thanks TT, sorry, I was quite vague with the question. Dang it we have been busy and Iw as a bit in a hurry.

My A/C system and compartment fan will not come on. I have checked all connections in console, checked them under hood too, so we are good there. Borrowed a relay from friends 82 and still nothing. Did not try another resistor, but if I remember, the fan should work on one of the out puts with out the resistor??

Would the compressor come on if fan does not work? Would the fan come on without compressor in circuit? I have tried all parts of console switch in vent, heat, and A/C. Everything appeared to be working ok until getting caught in a recent storm and no defroster, no paper towels, nothing, that was fun........It is the original fan as I found the car, not sure if ever replaced.

Thanks!

tt
 
If both the fan and the compressor will not work, the fuse is the common factor.
 
big2bird said:
If both the fan and the compressor will not work, the fuse is the common factor.
Click to expand...

Not to be too stupid, I call myself checking the fuses, but, is there a particular fuse I need to check, that I could have missed? Not to mention, at 6 feet, 200 pounds, its a little tough to get in there to check the fuses.

I've been through the wiring diagrams best I can. Checked the relay again and I am getting power through the relay, FWIW.

Thanks in advance.

tt
 
Does an 82 still have the single wire (connector) fan? If so, check the ground lug on the fan housing.
 
BBShark said:
Does an 82 still have the single wire (connector) fan? If so, check the ground lug on the fan housing.
Click to expand...

Yes, it does. However, he lost the fan and compressor.

Okay, I'll use an 81 schematic. If you have power windows, and they work, then your good from the fusable links, thru the ignition switch to the fuse block.
From the 25 amp fuse marked A/C, it feeds the controller.
If the fuse is good, and you have 12 volts there, the controller is bad/unplugged.
It seems highly unlikely both controller switches went south at once.
I suggest checking the 12 at the fuse block, and replacing the fuse. They CAN look good, and be bad. Been there, done that more than once.
If you have 12 volts there, you need to pull the pass side console cover, and take a look.
Your com,pressor and fan did BOTH fail, correct?
 
gr8vet said:
Borrowed a relay from friends 82 and still nothing. Did not try another resistor, but if I remember, the fan should work on one of the out puts with out the resistor??


tt
Click to expand...

The high speed relay bypasses the resister bank, but still relies on controller 12v to engage.
If you have 12v to the relay, and the relay is good, it's a controller circuit issue.
 
Checked all fuses, I do have power to relay at all points. Have power going through each leg of the resistor. Do have power going to the fan/blower, purple wire. Checked ground on fan. Controller was replaced about a year ago with one from Ecklers.

Looks like problem is pointing toward blower. After checking all and making sure all connections are good I have not started engine to see if AC clutch will engage. Not sure if you can make it engage or not without motor running?

Would loss of blower keep AC compressor from coming on?

I'll start up when it gets a little later, it's 4:45am here. I have a new blower in box from a couple of years ago, problem #3, where the hell is it?

Thanks again

tt
 
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gr8vet said:
Checked all fuses, I do have power to relay at all points. Have power going through each leg of the resistor. Do have power going to the fan/blower, purple wire. Checked ground on fan. Controller was replaced about a year ago with one from Ecklers.

Looks like problem is pointing toward blower. Yes After checking all and making sure all connections are good I have not started engine to see if AC clutch will engage. Not sure if you can make it engage or not without motor running? Yes

Would loss of blower keep AC compressor from coming on?No

I'll start up when it gets a little later, it's 4:45am here. I have a new blower in box from a couple of years ago, problem #3, where the hell is it?
Can't help you there.
Thanks again

tt
Click to expand...

It's still HIGHLY unlikely the comp circuit AND the blower quit at the same time. However, see if replacing the blower solves that issue. If so, the compressor circuit goes controller>pressure switch>comp clutch. A low charge will also cause the pressure switch to stay open.
 
Update.

I went in and rattled all the plugs and the contacts under the controller. Found the new fan in shop.

The relay is definitely bad (2 years old), the borrowed relay (26 years old) does work. I do have the compressor clutch kicking in now. The resistors are good.

The new fan works. The new fan WILL NOT work with the old fan ground wire???? But the new fan will work if grounded to the engine, by accident saw it spark as I had it laying on compressor. I would assume I have lost ground to the old fan, and it may work if grounded properly. My big ass hands will not allow me access. Good to have small wife with tiny hands that I will bribe to make connections over the weekend.

Man, what a bitch, I hate fooling with electrical and in these tight places. I hate to even ask how hard it is to change a blower out. Hopefully can come from underneath or through side vent.

Thanks for the help! You guys are great!

Maybe I'll have the AC going by the time summer is over :crutches:

tt
 
On my '72 I can change the blower motor without tearing the whole car out, but I don't have a expansion tank in the way....

this last time around I just flat wore out of cleaning that evap housing, and decided to cut the damn wheel well/fender liner out of there, it can be bolted in easy enough to make a patch panel out of it....

:crutches:
 
The ground is split in the harness to also go to the alarm switch, wiper motor, relay, blower starter ground bolt and another I can't remember.
If it has ever been wrongfully attached to the starter battery post, it may well be burnt thru inside the harness somewhere. Have found this before.
Good idea to upgrade that skimpy ground wire to at least 10 ga anyway. Will help blower speed a lot too.
 
Update

010752 said:
The ground is split in the harness to also go to the alarm switch, wiper motor, relay, blower starter ground bolt and another I can't remember.
If it has ever been wrongfully attached to the starter battery post, it may well be burnt thru inside the harness somewhere. Have found this before.
Good idea to upgrade that skimpy ground wire to at least 10 ga anyway. Will help blower speed a lot too.
Click to expand...

Dang good call.

I replaced the blower, took 15 minutes with the overflow bottle removed, at least something was not too bad to fix in here. BUT, The dang thing still does not work. If I ground the motor directly to the frame it works.

Got one for you, when I switch the AC control from off (left) to max cool (first position right), the lamp behind the wiper control comes on, I about laughed my a$$ off when I saw that. One other note: If I turn wipers on then off, they go into a spasm like they are cutting on and off and only coming up just past the hood. The only way to stop this is to turn key off. You can hear a relay in back clicking during this.

If I put my meter on the ground wire to the blower I am seeing 12 volts, so obviously you are right, the ground wire is burned into a hot wire somewhere in the harness.

The blower did prove to be bad, not sure if it caused all the other issues, but I am slowly working through them.

Thanks again for all the help.

tt
 
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DID YOU do anything with the starter/bellhousing recently??? if so, there is a wiring error, there is a black ~10 ga wire with a 3/8 loop on it, it goes to GROUND, as in engine block somewhere, and NOT the battery cable.....it is the ground wire for the blower, wiper motor, and relay......

that would explain the back feed light on your dash....

common error, and so I did it too, years ago, when that happened, I relocated that damn wire to up top on the intake manifold, no more of that shit....

:cussing::rofl:
 
mrvette said:
DID YOU do anything with the starter/bellhousing recently??? if so, there is a wiring error, there is a black ~10 ga wire with a 3/8 loop on it, it goes to GROUND, as in engine block somewhere, and NOT the battery cable.....it is the ground wire for the blower, wiper motor, and relay......

that would explain the back feed light on your dash....

common error, and so I did it too, years ago, when that happened, I relocated that damn wire to up top on the intake manifold, no more of that shit....

:cussing::rofl:
Click to expand...

No, have not done anything in that area. BUT, I have not looked in that area either since this problem has come up. All those wires are dang close to the header on that side, could very well have got hot and fused together.

Thanks, gives me another spot to check.

I Love working on engines, bodywork, painting, etc. Trouble shooting electrical sux. :hunter:
 
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