Chrysler Repair: 2002 jeep heater/ a/c problems

Question
QUESTION: Hi Roland , it's Richard and my 2002 Jeep Grand Cherokee is still have blower problems with the Heater. I went ahead and changed the fuses under the hood and dash and I did get some results. Still no blower for heat on any setting. The heat is there cause I can feel it but no blower. My A/c will work when turned on. Very cold and getting blower action . Not the greatest blower air but it does the cold air enough to cool off the jeep quickly. I want to ask you one more time before I spend the big bucks going to a repair shop. I trust you with the answers, more than the crooked repair shops we have here... Thanks again

Richard.

ANSWER: Hi Richard,
That is strange that the blower works on AC but not on heat.
My '06 manual is the closest I have to your '02 model so I cannot be sure it is applicable.
Based on that latter manual I wonder whether your system is a conventional control panel or an Automatic Temp Control panel? If the former, then I see no reason why the blower doesn't run whether you have heat or AC activated.
If you have the ATC control panel then I can suggest that the blower speed may be under the control of the ATC panel itself and that it chooses the blower speed based upon the temperature sensor for the air in the cabin (located in the control panel) as compared to the temperature that you have selected that air to be at. Try changing the temperature setting to see whether the blower speed changes or not when you are asking for heat.
Thanks for the rating and nomination.
Roland


---------- FOLLOW-UP ----------

QUESTION: I tried the A/C a minute ago and there is Cold air and It does come out of the vents but the faster I drive the more cold air comes out. When I slow down so does the air. On Cold mornings, I will turn the defroster on and while there is no air blowing, The faster I go The more heat comes out of the vent. And there isn't a blower sound at all with either AC or heat. More cold air comes out than heat.

Answer
Hi Richard,
The air flow being only related to the speed you are moving suggests that the intake air is not being controlled by the blower at all, i.e. blower motor isn't working. You would hear it run if it were.
In the '06 manual there is shown to be a 40 amp fuse, #1, in the power distribution center in the engine compartment which provides power to the blower motor. So I would start by checking all the larger size fuses in that box, if they are not labeled, to find the fuse for the blower motor power. There is also a relay in that circuit, but I don't know whether the '06 diagrams would be applicable to your year. But if there is no blower motor sound coming fron the underside of the HVAC box under the dash at the right hand end of that box, then you don't have any blower motor "action". The implies that the fuse for it is blown.
Roland