Initial stages were intermittant guages, check engine light, abs, door ajar, gas guage etc., warning lights on or off.

Now the transmission won't shift gears after a couple of stop lights....Have to throw it in N and restart the engine all together for it to start working correctly again.

Currently, whichever computer is malfunctioning is now draining my battery to the point where the car won't start if i leave it sit for a few hours.

Based on my amateur research, it looks like its the bcm/tcm/pcm???? If so which one? or could it be all of them?

My friend tried to pull a code off of the car but thats not working either. The odometer occasionally reads "NO BUS"..............???????? Please Help, thanks

 

"No Bus" means the computers cannot communicate with each other. There's a communication bus (wire connection) by which the various computers talk to each other and receive data from various inputs and send commands (such as "upshift now" or "register 50mph on the speedometer") to the things in the car that are controlled by the computers. Sounds like you have a serious wiring problem. Was the car involved in a crash at some point?

 

dcotter, thanks for the reply...The car has never been in an accident, in fact when i purchased it just over a year ago, everything worked just fine, no gremlins at all...

One very important thing that i forgot to mention that could have started the problem was while jumping it after sitting for a couple months...someone, wont name names, lol, put the positive and negative cables on the same post not knowing the neg post was 3 feet away by the windshield...Well this obviously melted the jumper cables but it didnt seem to cause any problems initially.

I'm no expert, but I don't think wiring is the problem because usually if its on open wire then you have a "consistent" problem vs. an intermittent problem...When I fire up the car its works like it just rolled off the showroom floor, gauges, tranny etc, work like something NASA designed . After several miles down the road however lights start popping up, gauges shut off, tranny goes into limp mode . Turn the car off and restart and viola back in business!!

So with all this said, I'm just trying to find the most economical and logical place to start...replace the BCM first? replace the TCM first?

 

Have you ever solved a computer problem by re-starting your computer? It works often enough on your PC to be worth an effort on your car. Try disconnecting the battery and waiting a few minutes before hooking it up again. The wait is necessary to allow residual voltage to dissipate. That might succeed in clearing out some befuddlement in your computers' brains. If not, I would not recommend throwing new computers at the car, because that could get very expensive with no guarantee of fixing anything.
You might consider taking it to a Chrysler dealer for a diagnosis. They will charge you $85 or so to hook up their DRB III machine to the car. They might be able to re-program a computer right then and there to cure the problem. They might say you need a new computer. If that's the verdict, then the first thing you should do is ask them if they will absolutely guarantee that replacing the computer will solve the problem. If they say no, then it's easy to walk away. If they say yes, it's still just as easy to walk away because you can find a replacement computer for about 15% of what the dealer wants to charge if you hunt one down on the web. Don't just buy a computer, though. Buy one that has been programmed with your VIN and odometer reading. I replaced my Sebring's PCM with one I bought on eBay for about $200 including proper re-programming. It has worked just fine for over a year.

 

Thanks again dcotter! From what i've gathered on numerous sites searching for good clues or even answers to solve my lovely gremlin problem, your advice about throwing computers in the car does not solve the problem 9 out of 10 times...That said I'm far more educated than when i started..

As far as resetting the computer, you saw in my first post that I have to take off my neg battery cable anytime my car is going to sit for 4 or more hours. If I don't the battery is flat dead. When I hook it back up and crank up the car I see interior lights that i didnt even know that I had, lol. Thing lights up like a christmas tree with no warning lights on the cluster whatsoever! Today it even stayed that way for quite a few more miles than normal because I had the cable off for 14 or so hours...But low and behold, back into limp , engine warning light etc. , same ol same ol .

Would Autozone be able to help? I know the have the ability to read codes but maybe not the equipment for my issues...One last thing, I did read something interesting about having someone do an IOD? Something along the lines of checking for a "pull" on the battery to determine the location of the gremlin....?

Thanks again, dcotter

 

You can do an IOD (ignition off draw) test yourself. You need a volt-ohm meter with DC current capability, but they usually can't handle more than about a half an ampere of current, so if yours has a big draw, it might be beyond the capability of the meter. With nothing on, no lights, key out, etc., there should be no more than 0.050 amps of current coming out of the battery. Disconnect the battery at one terminal and measure current through the meter between the disconnected terminals, if that makes sense. That amount of current represents what is necessary to keep the clock working and for the keyless entry receiver.
If it's more than that, you are drawing too much. Pop fuses one at a time to see which circuit is drawing the load. Once you have it isolated, you'll need to figure out what is causing it.
Wiring faults can occur where wires pass through steel if there's movement sufficient to cut through the insulation., or where wires bend and flex, like going into a door.
Wiring for the communicaion bus is thin as it carries data, not any significant amount of current. Maybe you've got a damaged harness that includes a bus wire and also a current-carrying wire that is shorting occasionally when it moves a certain way. Could also be a problem with a printed circuit board in a computer that breaks continuity when it gets warm and expands a little.
Autozone will usually read codes for you for free with an OBD II code reader. In your case, that may provide some guidance if the computer itself has an internal problem. A Chrysler dealer has a much more sophisticated machine, but it ain't free. Good luck.

 

start unplugging all the modules one at a time starting with the radio! the violet/yellow wire on the radio. when this wire gets grounded it causes these same problems. i just spent 2 days trying to understand how this works and finally found the radio as the culprit. but it can be any of the modules as they will create the same exact symtoms. it's the same thing as unplugging the bcm. all the modules communicate on this one wire. i could not find anywhere on the net a fix! so i'm sharing it!

 

start with your tcm first "now that i reread your post" !!

 

this wire or module being grounded will also drain the battery quickly. you can unplug each module at a time and turn the key on when its messing up.. it will show instantly!