Odd HVAC blower behavior, anyone got any ideas?

toy4everyseason · **Posted:** Sat May 28, 2016 5:26 pm

So my HVAC blower is on the fritz doing some crazy behavior. It will randomly cut out completely at all speeds and vent positions while driving. Sometimes shutting off the Jeep will resolve the issue for a short period of time but it will usually cut out again. I replaced the blower motor resister and it problem still exists.

Then it got strange, one day when it was working, I shut off the Jeep but the HVAC controls continued to have power. I then popped the good and gave the TIPM a good smack and it turned off. Thinking it's a stuck relay, I looked under the lid of the TIPM but I don't see a relay that is marked for blower. I called the dealership who told me the relay is built into the HVAC controls but that wouldn't explain why smacking the TIPM resolved it being stuck on. Any ideas anyone?

Scar0 · **Posted:** Sat May 28, 2016 7:47 pm

Your probably not going to like this...
A KA owner had a similar thing happen. Then while he was driving the TIPM caught on fire...
Click here to see the thread about it.

toy4everyseason · **Posted:** Sat May 28, 2016 8:21 pm

That's what I thought it was, I should ask the dealership if the TIPM is part of the power train warranty...my guess is no. Good thing I drive around with a tool kit & fire extinguisher.

Scar0 · **Posted:** Sun May 29, 2016 12:37 am

Keep a 10mm real handy, and don't park close to anything you care about till it is fixed.
One KA burnt up just sitting in his driveway. Right after he got done waxing it, if I remember right. :roll:

toy4everyseason · **Posted:** Sun May 29, 2016 1:37 am

I just confirmed its a loss of power from the TIPM. When the circuit is working as it should, I'm getting power to the back of the HVAC controls but when it cuts out...nada. I'm going to keep my HVAC switched off for now, maybe that will reduce the risk. Does anyone know the wiring diagram for the blower circuit & if there is a replaceable relay or fuse that controls it. I'm doubtful replacing a relay or fuse will help but hopefully I can pull it until I can get it to the dealership. Correct me if I'm wrong but doesn't the TIPM need to be programmed at the dealership?

Scar0 · **Posted:** Sun May 29, 2016 2:34 am

It's hard to decipher the diagrams. The HVAC controls B+ is from M34 via the run-start relay. But it looks like the blower gets it's power directly from the TIPM.
HVAC Plug C2 pin 1 would be B + for the blower motor. But I also see Pin 2 on the blower plug as a supply B+ directly from the TIPM.
I do not see a fuse or a relay associated directly with the blower motor.

lfhoward · **Posted:** Sun May 29, 2016 8:42 am

Toy, sorry for your issues. Having the TIPM on the fritz is more than unfortunate. I just read through Scar0's KA thread on TIPM's catching fire, and am a little horrified. I hope you can get a new TIPM soon before it has a critical meltdown.

I put a link to this thread in the KK's How-To's Index so folks would have it as a resource going forward.

Scar, do you know if a new TIPM needs to be flashed and programmed at the dealer, or is it something that can be installed out of the box by a careful DIY-er? Is the procedure for installing a brand new TIPM any different than for a used TIPM transplanted from a totaled (i.e., rear ended) KK/KA that already knows what kind of vehicle it is supposed to be in?

ajohns1288 · **Posted:** Sun May 29, 2016 9:31 am

lfhoward wrote:

Toy, sorry for your issues. Having the TIPM on the fritz is more than unfortunate. I just read through Scar0's KA thread on TIPM's catching fire, and am a little horrified. I hope you can get a new TIPM soon before it has a critical meltdown.

I put a link to this thread in the KK's How-To's Index so folks would have it as a resource going forward.

Scar, do you know if a new TIPM needs to be flashed and programmed at the dealer, or is it something that can be installed out of the box by a careful DIY-er? Is the procedure for installing a brand new TIPM any different than for a used TIPM transplanted from a totaled (i.e., rear ended) KK/KA that already knows what kind of vehicle it is supposed to be in?

According to the service manual, when a new tipm is put in, you turn the key ON for 12 seconds, then off, which allows the CCN (cluster) and PCM to program the TIPM with the required info. I'm not sure if this would work with a tipm out of a different KK, at the very least, you'd get a VIN mismatch, but that might be able to be programmed around.

Scar0 · **Posted:** Sun May 29, 2016 10:06 am

Actually it will learn the Vin# during the 12 seconds.
Used is pretty much plug and play. But it has to be from a KK(not sure if the 11+years are compatible with the 08-10 years, because of the bus changes.).
If you can get one with the same options even better. If it came from a rig with different options you may have to pay a dealer to activate them.
You guys are kinda lucky because you all have the same engine. And you don't have to deal with the J28 recall (TIPM wiper relay bypass).

New is a different story. If ordered thru a dealer with your VIN 50/50 it will come programmed and ready to go. On-line new, even ordered with your VIN, more then likely will come with no programming (Can't even start your rig). Dealer or on-line, you will need to ask specifically if it will come with your VIN specific programming already installed.

Instructions can be found in a link here. #17. Follow it to the letter.

toy4everyseason · **Posted:** Tue May 31, 2016 8:26 am

And the weirdness continues. I tried the old IT technique of turning it off and back on again and it has seemed to resolve the issue. I disconnected the positive post on the TIPM and reconnected it and it has been 6 different drive cycles and the issues have failed to return. I'm still doubtful that it stay that way but only time will tell if it's fixed or my TIPM will self destruct.

Scar0 · **Posted:** Tue May 31, 2016 9:33 pm

Glad to here it is working again. Hope it stays that way...

Odd HVAC blower behavior, anyone got any ideas?

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