No heat blowing unless...

Hey guys i think this is a common problem with the TJs but i wanted to confirm if anyone had the same symptoms and issues.

My heat wont blow on the lower settings and ONLY works on full blast. The guy at the local auto parts store said it might be some heater coil of wire behind the glove compartment (cant exactly remember what he said - but he also wasn't sure because he'd only worked on cherokee's) or the switch.

Has anyone had this issue before and did you fix it? How?

Hey Mike,
Sounds like the resistor is no good, should be an easy fix.
Make sure that the cavity where the resistor goes is free of debris.
Wet leaves and crap that gets into heater box will short / corrode new resistor.

Also be sure to look at plug to see if it is corroded or melted.
Do not turn on heater unless resistor is installed into heater box, resistor wont last long because it needs the heater fan to keep it cool so it won't burn out. .

Hope this helps ,,im pretty sure that is what is wrong. BUT, you never know...
Mark.

What Mark said is exactly what I was going to say.

Motor blower resistor. $5 on Amazon, install is kind of a pain but it's simple.

yup, resistor pack. manufactures have installed a bypass in heating systems to allow the blower to still work when the switch pack/resistors go bad. the high setting is the bypass thus it working on only high. Should be an easy fix. Im in millis if ya need a hand with it, lemme know.

You've got it, when you put it on high it is getting straight 12 volts and it should be bypassing the resistor.

Guys, Mike has a JK now!

/thread

That's right wow, what was I thinking. I guess I wasn't, hmmm.
Thank's Ryan, you're on the ball.

Markmmaark wrote:That's right wow, what was I thinking. I guess I wasn't, hmmm.
Thank's Ryan, you're on the ball.

Doesn't hurt to have the info on the forum Mark! Just wanted to throw that info in there though so nobody was offended if he didn't answer