No blower on heat....

[FiremanBrad]

Works on AC. But when the switch is moved to heat/defrost the blower for the heater doesn't come on. The blower works...I put 12v to it and it runs fine. The vacuum lines are still attached to where they are supposed to be. the motor isn't getting power from the switch...which is good. Any ideas??? I had a Ramcharger that did the same thing...it was the ignition switch. Is this a possibility here?

86 waggy BTW. Factory A/C

[grand_wag_85]

Do you have round or square gauges on your instrument cluster? 1986 was a changeover year. The Jeep should have a GM style steering column with a GM ignition switch(PN# LS442). Might be the resistor on the heater box.

[joe]

While trouble shooting keep in mind the AC blower motor is NOT the heat/def motor. The two systems use separate dedicated motors. The heater blower motor is in the eng bay at the heater core box.

[FiremanBrad]

I have the square gauges with the GM column. I haven't looked at the ignition switch. I will go by the parts store and get it and the resistor. I know the systems are seperate....that's why I couldn't figure why one blew but the other didn't. Thanks! Everything else seems to be working as it should. (on the AC anyway...;-) )

Thanks!!!

[lunchbox1671]

You could have a blown fuse, bad ground, or bad positive.