cold weather jeep problems (abridged title: heater is a no-go)

[superj]

Well, the cold weather has finally hit corpus and I guess the ol' jeep just isn't enjoying it that much as the blower motor has decided to protest cold weather by going on strike and doing a sit in. This is all fine and dandy but that is going to severly limit the jeeps usages as only I and my youngest son will enjoy driving in it still.

The facts:
Blower worked last time I drove it, day before yesterday.
Jeep gets killer hot when blower is working.
Jeep now gets a nice hot blast only when moving
No blower sound can be heard at any setting
No air can be felt on any setting while sitting still
There is a three wire plug that goes into red box hooked to blower motor
No wire in that plug gets power at any setting
Fuse is still good

Other interesting notes:
Blower motor looks to have been replaced as its not sitting in housing properly
No funny smells at all in jeep to indicate burned wires or resistors
I have no wiring diagram

I believe that is all the stuff I have come up with so far so if anyone has any leads, or a wiring diagram, I would be greatful for help. My tootsies are getting cold

 

[Jester32]

Sounds like the blower motor was on its way out and took out the resistor. Very common.

 

[superj]

that sounds logical but shouldn't it have blown a fuse or something? i am going to guess the fuse is good as the one that says heater checked good with the multimeter and i saw no other one labeled anything like heater, blower, anything. i have power on both sides of hte fuse too and didn;t really dig into it as i was at soccer practice and had only my mag light too see in the dark parking lot.

 

[clydethepirate]

Maybe it joined the occupy movement and isnt moving until warm weather returns.

 

[Jester32]

It usually won't blow the fuse. The motor over time will draw more and more current as it wears. And the resistor will eventually burn out. The fuse will usually only go if it's a dead short. Are you getting an output from the heater control to the resistor?

 

[superj]

i got nothing on the wire going to what i believe is the blower resistor. the resistor is the red plastic thing held onto the housing with only two screws that the wire hooks to, right?

i will dig into it some more after work today. i might have not been checking everything with the hvac controls and ignition in the right settings so i will reverify the wire checks in the light. if i pull that resistor and check for continuity, it should read good and an open would indicate a bad resistor, correct? also, how is the motor supposed to sit in the housing? and lastly, i read about a spade connector under the battery tray? if its unhooked, the blower won't work. i will check for that also

 

[Gennybro]

It may possibly have a fuse on the motor itself. Had a chrysler New yorker that I had thought the motor was gone on it,sold the car. Person that bought it told me about the fuse on the motor that had gone on it.

 

[superj]

ok, will try and check that too

 

[superj]

ok, rechecked all the settings and made sure the key was in run and no power to the three wire plug from the heater control, nothing to the spade wire on the firewall and the fuse is good and has power on both sides of the fuse.

 

[superj]

didn't get to check for a fuse on the motor though. felt as much of it as i could and didn;t fell a fuse any where on it but since i didn;t get it all, its possible there is still one on it

 

[superj]

Update: The waterpump started leaking so i changed that, which immediately caused the alternator to fail. somehwere during all the wire wiggling and belt tensioning, the heater blower started working again.