No blower speed control

OK, I'm desperate. I know its on here but currently its -20 and I have next to no heat. Before winter I was having issues with the blower speed controls.... Replaced the blower motor/resistor and switch, which was obviously melted. P.O bypassed the melted switch plug with insulated disconnects... Anyways it worked great until a few weeks ago. I got intermittent fan speed. Finally it quit all together. Fan comes on but only low extremely low. I purchased another switch and resistor to no avail. Then today I noticed the plug to the heater control had a pin loose. Just barely making contact. It was blk with a stripe. If I messed with it the fan would come on high...went to the junkyard today and grabbed a new pigtail for said connector and new heater control. Wired in the pigtail and hooked up new heater cont. Same shit.....fan comes on and blows but low only..... I'm stumped... Figured this would solve my problem......I've seen the writeup on using fuses etc.... But if it won't work now as it sits it seems there's another issue......

Please give me some input! As I'm freezing my sack off!

-Sean

It might help if you posted up what model year you have. There are some differences.

I have seen the steering column mentioned in one instance. I think there is the potential for an overload on the "ignition on" wiring that runs through the steering column. I haven't had to get into that myself, but that might be one place to look for interesting wiring problems.

95, but I'm getting power?

Hello?

I don't think anyone has a good answer for this one.

My best guess is that one of the parts you think is good is actually not good.

If you can make the blower motor run on high then it should not be the motor. The switch, the resistor and the wiring between would be the most likely suspects. You can start testing things with a voltmeter, or you can start jumping connections, or you can start swapping parts.

Or you could order a Willy Warmer.

Its gotta be in the wiring.......willy warmer doesn't sound half bad.......

have you jumped 12v straight to the blower? This would let you know if youre dealing with a blower issue or a wiring issue.

I'd try to run an ax 12v wire straight to batt. If fan kicks on then you blower is good. I'd work my way back from there. Can someone please post up a diagram(s) of the blower motor control circuit?

NorCalChris said:

I'd try to run an ax 12v wire straight to batt. If fan kicks on then you blower is good. I'd work my way back from there. Can someone please post up a diagram(s) of the blower motor control circuit?

Click to expand...

I think that Heat Mode Selector Switch is for Non-AC Jeeps. It's part of the climate control panel, not a separate switch as shown.

That switch symbol in the resistor block is a Thermal Switch. All resistor blocks have them. It will melt (open) if the resistor block overheats from low airflow passing over it or a very high amp draw on the block heats it up. It blows internally.

If you can, test the motor draw. If the blower motor draws too many amps it will melt switches and connectors much like you are describing. It many times will also run slow.


Just some food for thought.