I have a 1999 Chrysler 300M with a 3.5L engine. My Check Engine light came on and at the same time I lost my dash gauges and it will not shift out of first gear.
Computer Diagnostics done to extract the codes for the check engine light. The coeds were:
P0720 = Output shaft speed sensor error
P0731 = First gear incorrect ratio
P1790 = Fault immediately after shift
P0700 = Transmission fault code
Since this situation all happened at once it would make sense that they are related. After removing and testing the Output shaft sensor that is supposed to be at 800 ohms, and was showing completely open, the Output shaft sensor was proven to have failed. Replaced the Output Shaft Sensor ( $20.00 ) and cleared the codes. Test drove the vehicle and all is working normal. Customer happy.