05 jeep wrangler no air/heat when blower is on low

probably have a blockage in the heater core or heater hoses to the core

replace termastat

They are near the blower motor as the air is used to cool the resister, usually on the bottom of the blower housing.

BJ
I'm using the comment section of the original posting to communicate with you.
Pat

Ok, if you are trying to use your AC and its not turning on, odds are your refrigerant levels are low, the system will not turn on when low fluid levels are present so the system doesnt burn up the compressor.

If your blower motor is not operating, you may have a fuse blown that needs to be replaced, or the control chip that plugs into the blower motor (for fan speed settings) has burned up (easy fix).

If your climate control is not throwing out heat when you change the settings to hot, you have a leaky vaccume line and the vaccume pressure is not strong enough to open or close (depending on setting) your blender box. Although typically when a vaccume line springs a leak you will have issues with your selector switch as well (defrost, vent, floor)

Also pay attention to your temp gauge to make sure the thermostat is operating properly, and the engine is not over heating ro getting excessivly hot! If it is, then you need to replace the thermostat ($8 part)
and go from there. Also you should check your heater core, if it gets clogged or has restricted coolant flow, your system wont have the heat it normally did (if any) when it worked properly.

This is just a quick summery of the area's you should be looking into for the problems you are having! thanks for using Fixya.com and good luck, I hope I have helped make resolving your problem alittle easier

qss

Mine only works on the highest setting, did you figure this out yet?

Replace the blower motor resistor. You can unplug the fan till you get one. Usually located behind the glove box.

check fuse first, every jeep ive had had the same problem ,its the fan speed resistor,most are located on the heater core /fan housing.NAPA 25.00 PLUS SHIPPING.

the electric motor that open the heat door looses electrical connection there by the door stays on cold / it is located under the a/c heater assembly / which requires removing the whole dash and heater assy// also bleed all air out of coolant system
there are three doors / 1/ a/c heat 2/ mode /defors 3/ recurculation [email protected]