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I had all my brake warning lights on the tree go off today (ABS, Brake, ESP/BAS). I had the same issue a few months ago and took my 08 JKUx to the dealership. They changed out what they said was a "fused ignition cable" that led to know power to the alternator. They also installed a new starter after claiming the line was fried. I should also add that my horn goes off randomly from time to time when I hit the lock/unlock on the fob.

There are no codes popping on the OBD2 scanner. So I stopped by my local Midas and had them run their scanner and they said it's probably a PCM? issue. (I believe PCM. Is there also a CM?).

What should I do at this point? I don't have another grand to drop on what I now suspect was a band-aid solution. Can I change out the PCM on my own? I'm not a fan of electrical work, but will do it if I can save some bank. Also, I had some Hella lights wired up around the beginning of the year. If those were miswired, could that be sucking the life out of the electrical system? The lights were wired into my fog lights switch.

What's the difference between TIPM and PCM?

Help and advice are appreciated. My Jeep waited until is was paid off and decided to have electrical gremlins. I'm not sure what to make of the problem at this point.

I'm also under the impression the vehicle is still safe, but I don't have the benefit of ABS or ESP/BAS).
 

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If it hasn't been already, make sure to have your battery checked. A worn out battery can cause all manner of strange behavior with warning lights going off randomly. It could be something as simple as corrosion on the terminals that periodically causes interruptions.

If your jeep computer is bad, I'm pretty sure the only solution is replacement.

Also, if your alternator wasn't getting any power to the jeep, then you were running all systems off the battery. Especially if the battery is older, that heavy drain could have been the final straw (unless it's an Odyssey or similar). This could mean that even when you replaced the alternator, you'd still be having these problems until the battery was replaced.
 

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If it hasn't been already, make sure to have your battery checked. A worn out battery can cause all manner of strange behavior with warning lights going off randomly. It could be something as simple as corrosion on the terminals that periodically causes interruptions.

If your jeep computer is bad, I'm pretty sure the only solution is replacement.

Also, if your alternator wasn't getting any power to the jeep, then you were running all systems off the battery. Especially if the battery is older, that heavy drain could have been the final straw (unless it's an Odyssey or similar). This could mean that even when you replaced the alternator, you'd still be having these problems until the battery was replaced.
Thanks for reminding me. What kicked off this entire ordeal in June was the battery died. That led me to figuring out the alternator wasn't charging. So both of those were replaced in one evening. The next morning, the entire vehicle died on me just after all the warning lights popped off. I changed batteries again and took it to the dealership. There they installed a new starter as well. I mistyped in my original post and should have said I installed the battery and alternator and the dealership installed new wiring and a starter. (That's been corrected now).
 

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Yeah....troubleshooting that could be time consuming. The fact that your ABS and ESP lights are now consistently on makes me think one of those sensors is now bad. The dealership can certainly check if they're working right. Typically bad wheel speed sensors will cause the ESP light to trip and sometimes the ABS. Bad steering angle sensors can also cause similar issues. They don't usually make your red brake warning light go off though. Since your brakes still seem to work fine, then either the computer's bad or it's getting bad information (sensors).

I'd be curious what caused the ignition cable to fuse in the first place. Perhaps it also caused damage elsewhere. My experience with dealerships has left me less that confident in their motivation to be thorough.
 

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What's the difference between TIPM and PCM?

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TIPM :Totally integrated power module (mostly mechanical switching)- Fancy word for screwed up fuse/relay box. Which was Daimler's parting gift to Jeep.

PCM : Power control module ("smart" equipment)- is more a brain that distributes power/ground to circuits when requested.
 

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Discussion Starter #7
TIPM :Totally integrated power module (mostly mechanical switching)- Fancy word for screwed up fuse/relay box. Which was Daimler's parting gift to Jeep.

PCM : Power control module ("smart" equipment)- is more a brain that distributes power/ground to circuits when requested.
Is there any chance when I had my off-road lights wired up that they could have messed up the PCM?

I had the engineering class at my school do that one day as a project one morning last spring.
 

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Is there any chance when I had my off-road lights wired up that they could have messed up the PCM?

I had the engineering class at my school do that one day as a project one morning last spring.
PCM not likely unless they went hugely the wrong route. TIPM, possibly depends on how they routed the wires and whether or not they piggy backed off an existing circuit and overloaded it.
 

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How does one test if the wheel speed sensors or steering wheel position sensors are bad?
Is that a dealer only issue?
2 different things. Wheels speed sensor can usually be tested via a voltmeter.

Steering angle sensor needs a diag scan tool either dealer or shop. Or well off mechanic.

What exactly are you trying to diagnose?
 

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Is there any chance when I had my off-road lights wired up that they could have messed up the PCM?

I had the engineering class at my school do that one day as a project one morning last spring.

Just for grins I'd disconnect those lights to see if it helps.
You mentioned them being wired through the original fogs.
They aren't your only issue, but may well draw more amps than the stock lights and make the buss system rear it's ugly head.
 

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2 different things. Wheels speed sensor can usually be tested via a voltmeter.

Steering angle sensor needs a diag scan tool either dealer or shop. Or well off mechanic.

What exactly are you trying to diagnose?
Whether it is a failed wheel speed sensor that is causing my Xmas light show or if it is the steering wheel position sensor that is causing my issues.
 

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I know of a similar case with a 09 JK. The issues started with a bad battery, after replacing it all kinds of lights went off on the instrument panel. The owner went to several shops and to the dealership and all narrowed it down to two possible causes, the TIPM (Fuse Box) and/or the instrument panel itself.

So since the vehicle was heavily used and abused over the years, the owner decided to start with the TIPM. He replaced it, which has solved some of the issues he had with the Jeep but still, the instrument panel was going crazy. So he went back to the dealership and they replaced the instrument panel itself, afterwards all went fine.

Here are some other symptoms he was facing before replacing anything, so you can compare to yours. If the vehicle starts, it goes normal for a while, when all lights goes off, the vehicle start to act weird including shaking and loosing power and eventually the engine dies. Also, if he leaves the vehicle for a while and start it again, it would start but again not for long.

So my assumption in his case would be that the faulty battery and whatever work have been done on the TIPM has fried it and eventually fried the instrument panel.
 

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Whether it is a failed wheel speed sensor that is causing my Xmas light show or if it is the steering wheel position sensor that is causing my issues.
Of the 2 options it's most likely ABS, however stating that there are no codes, were just engine codes checked or entire vehicle for codes? Most base code readers only pick up engine codes. Not ABS, Steering and traction control, or an other systems.

It could still also be alternator related since you said the fuseable link(?) was repaired but the alternator is the same piece. Though usually the battery light would normally come on.
 
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