Heater air fan, no air blowing, noise starting without contact

[mickeypowa]

Hi guys !

I have another problem :

I have no AC anymore on my car, but I would like my heater fan to work. It's not because I'm cold (its never cold where I live) but when it rains I would like to have some air blowing to prevent fog.

Here is a video explaining the problem :

When I bought the car, the owner told me the ventilation was not working.

When I checked the fuse panel, I saw there was lacking one fuse, I put it on and I could hear a motor working right next to the blower motor. I can hear the sound whether or not there is contact.
I have unmonted the blower motor and there is still the sound of motor so it must come from another thing.

Have you some ideas of what it could be ? I would like to stop this motor noise!

I have no air blowing from the vents when I put it ON on the dash switch, the blower motor don't run..
I tested the blower motor appart directly to 12V and it's working !
so there must a problem with the switch ou a relay ? what is the resistor ?

Thanks !!

 

[mickeypowa]

I have some news :
for the noise I hear, I don't know what is doing that but I found a connector coming from under the blower fan that make it stop when I disconnect it.


I have tried to put 12V directly on the blower motor when it's in place. I have the defog vent which now blows !! but not the other vents, even if I move the button on the heater control panel... Maybe it's stuck in defog position ?

I am thinking about a simple solution : bypassing all the system and maybe put an aftermarket switch on the dash to give or not 12V directly to the blower motor... as I only need defog air.. what do you think ?

The resistor is the connector just next to the blower motor, what is its use, because it seems connected to nothing but its plug.. ?

 

[Texas82GP]

There is an elecrical connector near the rear of the passenger valve cover that is routinely burned up.

With respect to the air only blowing out the defroster vents, usually it means the selector switch on the dash is getting no vacuum. Otherwise, sometimes that switch is leaking vacuum. That switch is available.

 

[mickeypowa]

this relay gets power from the resistor thank to the blue wire and from another big pink/red wire.
The blower motor is connected to this relay by the purple wire but get 0 power.
maybe this relay is not working ?

I have checked for the burnt wire behind the engine but nothing to declare. There is only this big pink/red wire which goes to the relay and gives 12V and another little green wire.

For the vacuum, I don't understand, is it fixable ? how ? or must I change the whole selector switch?

 

[Texas82GP]

Troubleshoot the electrical concern with a wiring diagram and a multi-meter. It's the only way to diagnose it for sure.

On the vacuum switch, you don't have to replace the entire control panel. The vacuum switch is separately replacable.

 

[mickeypowa]

I have not a detailed wiring diagram..
but all I know is that I have 1 always hot wire and 1 hot on ignition wire going to the relay and then the purple wire going from the relay to the motor is always at 0V.
but what is strange is that the voltage on these hot wire doesnt change if I put on high speed or low speed..

for the vacuum switch : is it this part :
http://www.ebay.com/itm/ACDelco-003...m58a903582d:m:mbCMgTsKrvMZo-Xspqd_EVg&vxp=mtr

 

[Texas82GP]

Could anyone please post a link or a wiring diagram for a 1980 Cutlass, HVAC system?

 

[mickeypowa]

thanks a lot for your help !!

I found that on the forum it seems to be the same as me:

the red wire is always hot
the blue wire is hot on ignition
the orange wire is hot when I put the switch on high speed

I just put it back together and now it works !!!! I don't know why, maybe there was a bad electrical connection somewhere...
SO now it works in low, mid low and mid high position...
I can't totally stop the ventilation, when I put on off it stays on low.

When I put on high it doesn't work... the orange wire is hot when I put on high so its strange..

 

[Texas82GP]

It is normal for the fan to run on low speed even when the system is turned off.

Check the blower motor resistor for the lack of high fan speed. It is right next to the blower motor under the hood.

Glad to hear you are enjoying some success!

 

[ed1948]

It is normal for the fan to run on low speed even when the system is turned off.

I think GM called it 'Flow Through Ventilation' in the sales brochures.