2002 Chrysler Sebring 3.0 Auto. Shifting problem

I just picked up a really cheap Sebring from a lady who had no idea what was wrong. Now I have no idea whats wrong so hopefully I can get some help. The car has the 3.0 lxi package. Automatic.
The issue is this: When You put the car into any gear to start driving, the car will not move until 3k rpm. And when it does move it shifts hard and it launches. If I am driving the car fast keeping the rpm high when it shifts it will shift very smooth but drop below 3k and it start to hit very hard down shifting and up shifting.
Also the car will not connect to a computer to read codes.
I fail to believe that this requires a whole tranny especially since it was granny driven and only has 90k on it.
Any insight would be awesome guys, Thanks
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Finnally got the car to connect to a computer and these codes where pulled:
p0135, 0141,0743,0733,0731,0720
Can the p0720 be linked to the the improper gear ratios?
I'm dreading that this is a bad transmission. To me it doesn't seem like it is.
once again any input is awesome.
2002 Sebring Lxi, 3.0 Auto