My 2004 Jeep Grand Cherokee limited has a heater issue. Even on high temp only cold air from drivers side. Not overheating. Pass side has warmer air

when heater is on blowes cold air on drivers side and hot air on drivers side

This is a common problem with WJ Grand Cherokees, it's called a "Blend Door".

In the heating and cooling system you have doors that open and close to give you warm and cold air and a mix of both.

What you have is an arm that pulls a door with peg on top, the peg tends to snap off. As you said your dealer replaced the blend door or doors I would take it back as is has blend door all over it.

Yahoo and youtube "jeep grand cherokee blend door repair"

I had a 02 limited blend doors issues (note the issueS) and was lucky to have it still covered.

I do hope this helped.

this model has a couple of possibilities, updated heater control panel which is quite an expensive guess also the blend doors located in the heater casing break also an expensive repair as dash needs to be removed t gain access, would advise dealer visit first to confirm correct fault.

the grand cherokees have a tendancy fot the control doors inside the heater box. they do make a update kit on ebay. most of the require removing dash but some have instructions to cut hole in heater box and replace doors from there.check ebay for blend doors. alot of sites have video instructions on how to fix

this fuse is of high rate and must be found under the hood and most probably not in the cockpit.

try flushing out the heater radiator core.remove the two pipes and put a hose on the conections and keep reverseing flow.dont forget to top up with pure antifreeze,

U will need to replace the pass side air temp control blend door acuator motor.

The blend door on the passenger side has broken. Jeep has made a replacement section for the heater box assembly so you don't have to buy the whole thing. You will need to remove the heater/A/C box to replace the part. I have done quite a few of these repairs to fix the problem

Try heatertreater.net. It's easy and worked. $130 well worth it.

Pass. side blend air door motor is probably bad.