Chrysler Repair/1997 chrysler LHS: trans limp-mode/now dead short
Before I took my car to have the transmission rebuilt, I had no problems at all. There weren't even sign of transmission problems until it downshifted into I think second gear while driving at a speed of 70mph. It wouldn't shift anymore and I hobbled it another half mile to get off the highway, then put it in park and shut it off. It wouldn't start again due to the power being completely drained, which confuses me, so I had it towed home. Later on when I had it towed to the shop, I put another battery in it, it started, and I drove it on to the street for the tow truck. The shop rebuilt the transmission and said it drove fine on the test drive until all the gages messed up,stopped working and the car shut off. It wouldn't start again cause it was dead. They told me it has a dead short in the dash but I don't feel confident about their diagnosis so I really don't want them tearing in to my dash or my wiring cause that's a big can of worms to open for somebody if they still don't fix it. What could be the cause of this? Keep in mind that the battery I used to start it with was out of my roommates' car so I switched back and I assume they are using my old battery that was in it when the transmission went out. I never tried charging it or jumping it so I don't know if it's any good, but I've stopped by a couple of times to get something out of the trunk and there was no power to the button.
I would be inclined to get a brand new battery or recharge the old battery and see whether that fixes the problem enough to get the engine to start and drive. If that doesn't work then you would need to do some testing of the battery current draw or resistance reading to ground of each of the fuses in the power box in the engine compartment to see which of the circuits is causing the short they claim exists. I would ask the shop to show/name you which circuit is dead shorted (find out which component or fuse operates the circuit that shows a short. Tell me which circuit "in the dash" is shorted according to the shop. Then we can consider what might be the cause and what might be the fix.
Do you have a volt-ohm meter and are you interested in checking it out yourself?
Was the transmission rebuilt or specifically what was done?
I even wonder whether the transmission needed to be rebuilt because this history suggests that the original downshift to second gear may have simply been an electrical failure of the circuit that operates the electronic transmission's power relay which of course will cause it to go into 2nd gear as a self-protective strategy that is built-in to the vehicle (called 'limp-in mode').
Do you trust the shop? If not, either you would want to find a trustworthy shop that had the wiring diagrams for the vehicle and tow it to them and let them find the electrical problem OR you can do it yourself with a volt-ohm meter where it sits now. Then sort out the question of the transmission repair being necessary or not and possibly seek a refund/small claims court restitution.
But first take out the old battery and either get it charged (if it still under warranty) or replace it.
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