Sooooo frustrated.
Chrysler diagnostics showing NOTHING.
We did a software update.
192,000 mi
Car can SLAM down into 1st gear with no warning or run perfectly fine FOR 30 PLUS MILES.
HELP!
Are we looking at a new transmission or tcm module?
How do we narrow this down?

 

Chrysler diagnostics showing NOTHING what does this mean you have a star scan or a drb3? do you mean it shows no codes? no codes mean there is noting wrong with a sensor. does not always tell you there is an issue with the trans.

 

I don't know how to answer your response.
I was told they did a diagnostic. That's it. There were a couple codes but nothing related to trans.
They drove it approx five miles with no issues.
They are GUESSING to replace the trans
No guarantee.
I'm asking here to help us trouble shoot what it might truly be.

 

we're going to need more data.
what else happens when these apparently errant transmission shifts happen?
dash lights? gauges? PRNDL display? speedo? tach?
does it stay locked in 1st? does it shift back to an appropriate gear quickly?
are there any remediation steps you have to take after the event occurs?


I could spitball and say... if the computer suddenly thinks you're not moving (or not moving fast even, and be wrong regardless) it could decide to drop into 1st gear.

 

There's no warning you can be clipping along at 40 mph or 65 mph and all the sudden it down shifts and you're thrown forward and yes the tach goes up of course.. because well your accessing a lower gear at higher RPMs that it's not designed for.
No lights come on on the dash at the time. It's completely random. My husband can drive it 34 miles to work and it not do anything wrong. Or he can pull out of the driveway and it starts downshifting before the end of the drive. It can stick like that for a little while you can put in a neutral rev it a couple times it might shift back into its regular gear or it might be stubborn and stay stuck and we have to drift off the side of the road put it in park wait a few minutes and try it again.
You're throwing out a lot of letters and stuff that I don't understand in your response I hope I'm not confusing you.
He did a filter change and a fluid change. He did not flush the system. But the guy at the dealership doesn't recommend that at this point.

 

So THEY is a Chrysler dealer? or the used car dealer you got the car from? IF an actual Chrysler dealer yeah they would have been able to see why the trans is put into limp in mode AKA the lurch forward and stuck in second gear. A Chrysler dealer would have access to the TCM side and see the CVI values last shift pattern and freeze frames so need to know who THEY are that your posting as to where you took it. And also did you pay for a diagnostic or was this just a free inspection?

 

Paid diagnostic at a legit Chrysler dealership.

 

I did say CHRYSLER DIAGNOSTICS and "guy at the dealership".
and we purchased this vehicle from and individual almost two years ago not a used car guy.

 

take it to a different dealer a star scanner will be able to detect issues