Baystate Jeepers

So.. Driving to work the other morning and a guy starts flagging me down. I pull over and he let's me know my brake lights are whacked and if I'm using my blinkers then they aren't working at all. I thanked him and carefully drove the rest ofthe way to work.

At work I got a good look at what they were doing. If I had my running lights on everytime I stepped on the brakes they would just flash for a tenth of a second. The third brake light worked fine. If the running lights weren't on it was a 50/50 shot that they may light or they may just flash. If I turn on a blinker then sometimes it would blink but if I hit the brakes at the same time the tail lights would go out. Huh...

I hit the All Data website and download some schematics to my Jeep. I start checking grounds, all good. Checking for 12v signals at the plugs and they are as inconsistent as the lights show. Check the wiring back to the TIPM and all good. TIPM output at the harness connector mimics the lights. Check the brake light switch input to the TIPM and it is solid.

So bummer! The TIPM is bad which isn't real unusual I guess. Call the dealer and it's $850.. which sucks enough on it's own but then add in that the part is currently unavailable and the next availability they show in the system is mid to late Nov! Ugh! So then I looked around on Ebay, Car Parts, etc... there are a few rebuilders who repair them for $430 with a short warranty and one new old box item for $650 that is being sold by a dealer but it's a superceded item.

So now I have to decide my course of action but in my researching device this thing along with the Jeeps ECU control EVERYTHING! And I mean EVERYTHING! Beep the horn? Wiring goes through the TIPM to the horn. Windshield wipers, all door window controls, interior lighting, dash board controls and instrumentation... everything! Good luck if it ever fails hard! We are screwed! By the way... the one for my Jeep has been updated and superceded 5 times! Thanks FCA....

I had something similar happen maybe 10 yrs ago. The wiring harness rotted and I actually had to get it towed. Good luck.. mine wasnt as bad as this, but it still cost a few hundred dollars

So I decided to purchase a rebuilt TIPM for now. Has a 1 year no questions asked warranty. I might send mine out for repair as well. The repair work to fix it and upgrade the internals is just over $200.

Fingers crossed!

So the update of my TIPM adventure saga continues. I received a re-manufactured TIPM yesterday. Disconnected the battery, hard reset the ECM and installed the TIPM and programmed it. Jeep started right up and all dash indicator lights out. Step on the brakes? Bummer! No different.

At least I now I have a spare TIPM! hahaha..

Well that kinda bites, did you check all your connectors to ensure nothing is broken or just slightly disconnected?

pirahnah3 wrote:Well that kinda bites, did you check all your connectors to ensure nothing is broken or just slightly disconnected?

I run all aftermarket lights on the back of my jeep so I really went through everything. But.. you are partially correct in the connectors causing the problem. Read the next post!

So, let me tell you the adventure I have just been on. My inspection sticker in was due last month. The day I'm bringing the Jeep in for a sticker a person flags me down to let me know my rear brake lights aren't working correctly. It appears that as I stepped on the brakes they would flash quickly and as I let off the brakes they would flash again? That's odd... To add a little more to the story, if I turn the blinker on then all the lights go out. This also isn't consistent. Temporarily the lights would work fine and then they wouldn't again. The only light that seem to work consistently is the third brake light. That seems to work fine. So here is what I found and the chase I went on to find it.

I started by just replacing the brake switch. For $11 it was worth just doing. What I did think was odd was that when I disconnected the switch the brake lights came on fine? Plug the switch back in and it would do the same thing. Why did they come on solid then? No idea. But it certainly wasn't fixed. So I pulled some wiring schematics from Alldata and started looking at the circuit and what would affect both the brake lights and the turn signals at the same time. I chased grounds and pinned out harness connectors. Put the multi meter on everything I could and looked at all the signals in and out of the tipm back to the lights. I kept finding all sorts of small electrical measurements that didn't make sense. For example I would get voltage feedback in the grounds when I stepped on the brakes. But it wasn't there when I turn the blinkers on and it's the same damn bulbs? So eventually the only thing I can connect the dots too is the TIPM. I figure since it's controlling the blinkers by just flashing the brake lights that may be something in that circuit is crapping out. So I find a guy online that rebuilds TIPMs and purchase a rebuilt unit off of him. I get it all installed and bummer... not fixed! Where do I go from here? So now I'm literally untaping wiring harnesses with the entire interior the Jeep torn apart and half the dash removed. Everything checks out good! All except that voltage feedback I'm getting on the ground circuit when I step on the brakes? Where the hell is that coming from? So I finally found it...

The only thing that works on the back of the Jeep is the third brake light. I want to say right now that I don't have any factory lights on the back of my Jeep. None of them! So why is the third brake light working but nothing else is. So I start taking a closer look at that circuit. The third brake light comes directly from the brake light switch and doesn't go through the tipm like the rest of the lights. But thankfully I decided to look a little deeper. The third brake light on my Jeep is a Poison Spyder brake light/plate light. I wired this to a 4-pin Deutsch watertight connector that also supported a couple reverse lights I added to my tire carrier. My watertight Deutsch connector turns out that one side of it was not so watertight! You could break the connector and it was dry but when you took the connector apart there was water inside of 1/2 of it. When I stepped on the brakes because the water was in the connector it would feedback through the ground but it would also feedback through the reverse light circuit. I spent so much time trying to figure out why there was voltage feeding back through the ground that I never noticed there was voltage also feeding back to the reverse lights. My rear tail lights are called dual-function LEDs. There is a running light, a turn signal, a brake light, but then also the reverse lights. All wrapped up into a 19 led 4" round housing. The red LEDs turn white to become the reverse lights. The voltage feeding back in the reverse circuit was enough to activate the dual function but not enough voltage to actually light the lights so it made them just go out. So I dried out the connector and sealed it up and all the problems went away! This took a week and probably 10 hours of diagnosing to fix on top of money I'm never going to get back that I spent on that tipm. Hey, but at least I have a spare tipm!

Now to finally go get my inspection sticker!

Glad you figured that out. What a pain in the butt.

Glad you got it solved, get her done!

Thanks! Trust me.. no one is happier than me that I got it sorted out.