I have a 2001 Jeep Grand Cherokee Limited 4.7L. After a couple weeks of the HVAC blower cutting out for short periods it quit working. I removed the blower motor and it works when I apply 12 VDC. After some more looking I found that the connector to the blower motor control module was melted at the black wire location. I've read online that this is a common problem. I see that there is a pig tail connector available at the auto parts stores that can be spliced in if I cut off the melted one. I was told in a phone call to the local Chrylser dealer that there is a design change for this that involves a wiring kit and a resistor. I have the dual zone climate control so I'm assuming that the resistor is the blower motor control module. I was also advised that this is not something that I should try to fix myself.Can you tell me what is involved with trouble shooting this and making the repair and what parts I will need?Thanks
Country: United StatesMake: JeepModel: Grand Cherokee LimitedYear: 2001Engine: 4.7L
Hello and welcome to JustAnswer!
You're using the correct terminology for the part but it sounds like someone at the dealer wasn't. A resistor is used on a manual temperature control system, your automatic system uses the blower motor power module. A resistor steps down current to give a few different fixed motor speeds, a power module gives variable speed control.
The power modules on these did give quite a bit of problems, and yes there was a design change. To completely fix your problem you're going to need to replace the power module and the connector. If you just replaced the connector (if you could even get it out of the module) you'd only be repairing half of the actual problem. Overheating and a poor connection at the module are what caused the connector and wiring to overheat.
The kit available from your dealer will come with a different style power module, an adapter plate to mount it to the heater box, a replacement connector, and a jumper to go from the module over to the blower motor. The new style power module is actually the same part used in the Chrysler RS body minivans and has more heat sink area to keep it cool.
Replacing it just involves cutting your old blower motor harness and removing the two screws that hold the module to the box. Once the old one is out then you'll install the mounting adapter to the heater box, which is just a piece of plastic held on with two screws. The old module is larger than the new one and the adapter takes up the space. With the battery disconnected you'll need to cut the old connector off and wire the new one on. Once the connector is wired up then there will be a two wire jumper that goes from the power module over to the blower motor. When you're done you may find that you have almost no air volume with the blower motor on high - if this is the case you'll need to pop the lock wedge out of the blower motor jumper connector and swap the wires around. For some reason some of these jumpers had the wires swapped and it spins the blower motor backward causing very little air volume.
If you normally do some somewhat basic repairs then you'll be able to handle this with no problem. The hardest part, which isn't hard at all, will be soldering the new connector on. It takes about a half hour for me to do the whole job, I wouldn't expect you to spend more than an hour on it if you've got a bit of experience with minor repairs.
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Thanks for the thorough answer. I have a friend who is a Chrysler employee in Michigan who may buy the parts for me to save some $. What should he ask for at the parts dept to get what I need?
He'll just need to ask for the power module and they'll know what to get. I'm sure he's familiar with it and they will be too. When the parts department looks up the power module they will find that the part number changes when they run it in Chrysler's system, and at that time they'll get the part numbers for the rest of what you need to install it.
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