Heater

[shanezoid]

I had a buddy of mine who is great at electronics check the relay and the resistors and he said both were fine so I guess the switch is the problem. Thanks Shanezoid.

 

[85 Cutlass Brougham]

The first thing I check is the power at the motor. If that checks out, I work my way backwards to the dash switch. This way, when you find the component that is receiving power but not sending it, you have found your issue. If you find that there is not a component that does not output, you know that the wiring has a fault in the section between it and the next component that does not receive it.

 

[foxtrot]

Does this schem apply:
http://www.maliburacing.com/wiring_diag ... tioner.jpg

 

[foxtrot]

I've had some time to think about this and now recall what the REAL issue was when I had this problem ~19 years ago. I remember doing the "shotgun" thing and replacing the blower switch but that didn't fix my problem. I then took a more methodical approach with a volt meter and found that I didn't have 12 volts at that relay behind the AC dryer. I found a bad connection and that fixed my issue...

 

[shanezoid]

So the the relay is for the high position on the switch because every other speed works? Thanks Shanezoid.

 

[foxtrot]

When the relay is energized (via the high speed setting), it directly connects the 12v high current source to the fan and the fan spins at the higher RPM. When the relay is not energized it is connected to the fan thru the blower resistor for the other lower speeds. I would make sure that 12v is present at the relay. If the 12 volts is not present it could be a bad connection or a bad fusible link.

 

[foxtrot]

Shanezoid,

Did you ever fix your issue?

 

[shanezoid]

Sorry about the absence we took the kids to the beach for the weekend so I will start on that first thing tomorrow and let you know. Shanezoid.

 

[Brick442]

My fan isn't working on high right now either. I hear that if the red wire in the pic below isn't hooked up it won't work on high. What is this connector? I found it coming out by the blower, I just don't know what it connects to. I cut a lot of wires out and trying to figure out where the wires on the right (male connector) are coming from. This pic isn't from my car.

 

[foxtrot]

Cut wires?

In the schem that I posted, the red wire that goes to the relay is the high current source to the fan thru the relay...