I just purchased a 1999 Jeep Wrangler Sahara about 4 days ago. 6cly with 5 speed trans. It runs great with some minor issues. Yesterday, I had only high speed on blower motor for A/C and heat. Inquires told me to check the blower motor resistor and sure enough it was all corroded with leaves and dirt. Today, I purchased a replacement resistor from Pep Boys. Came home and installed according to easy directions received off youtube including removing negative teminal connection to battery. After install and reconnecting battery, now I don't have any speed on A/C or heater. Before the fan speed switch felt "resistance" at the high selection now it is just sloppy whether on, off, low, med, or high. Help?
Do you have a simple muti-meter? You most likely have a poor ground and I would start there. Other things come into play but most of the times it's the ground, sand off a liitle patch where the unit fastens down.
Just for shits and giggles check the fuse.
The resister case is ground so just mounting it to a bare metal surface good mounting screws is good. If you have a multi meter you can set it to ohms and touch one lead to the case and the other to an insulated terminal (or to each one) and read the meter for an open or closed circuit. I can instruct you later for all the auto uses.
Sounds like you're hands on and in that case you can get a free multi-meter at Harbor Freight. A coupon for a free meter can be found near the back of many mags such as Motor Trend, Car & Driver, Popular Science, Popular Mechanics and Todays Handy Man to name a few. If you don't have a coupon then it will cost you $6.00. You can get these meters , depending on what they can do for upwards of $800.00 with an without attachments.
You say you felt resistance in the high position but now it feels sloppy when turning the switch? If that is the case I would pull the knob off and look at the back of it, they tend to crack so turning the knob does not actually turn the switch.
If it is the knob then you can get new ones online, but even those at the dealer are only like 5 bucks each. I just recently had to replace 2 of my 3 for this very reason.
I think I may have solved the problem. Got a helpful video from youtube on a similar problem. When I took a look at the switch and speed knob I found more problems that I have corrected. For now I'm back in business! Here is the link for the hlepful video:
Problem #2, after resistor fix, was the control knob, just as HardeMods suggested. When I removed the bezel and pulled the panel pieces of the backside of the control knob in a crystal blue color came out. The knob was loosely spinning around on the switch shaft. Fixed that and knob works fine now. I have A/C and heat. Thanks for the help!
I have a 99 jeep wrangler and have been racking my brain on what is wrong. Got a lot of good advice on switch or resistor pack being bad. Had my glove box area alll apart, got frustrated and took it to my mech. within 5 minutes he found thr problem. it turned out to be the 3 wire plug on the right control knob for the heat vent selector(the one that has the air tubes on it) had the key power on blower speed on high, and when he grasbbed it the fan came on. the plug on the side had been over heating. plus the resistor pack is bad. only high heat. replaced the terminal connectors on the plug that melted. resistor comes in tommorrow. but least i have high heat.
After reading the posts, replacing the motor and the resistor, my other problem ended up being the plug in on the vent controller switch. I turned the fan switch on high and wiggled the plug in on the controller switch, next to the air hoses, and a puff of smoke came from the plug and then the fan started. I removed the plug from the controller switch and cleaned it up, I then put it back together and everything ran perfect. Finally cold A/C.