P0700, P0720, P0731, P0736

Question

Friend has 2003 dodge caravan 3.3L V6.

Has fault codes:
P0700- transmission control system malfunction
P0720- output speed sensor malfunction
P0731- gear 1 incorrect ratio
P0736- reverse incorrect ratio

Also the speedometer is doing wonky things. We had the van in park and the needle was waving around between 20 and 30. We replaced the output speed sensor but it didn't seem to help.

Answer 1

Hi There I have the same issue and found out that the Alternator was causing the spike on the odometer. Just Disconnect the harness at the Alternator and start the vehicle and when you place the vehicle in drive, there should be no more spike on the odometer. just note since you disconnected the harness at the Alternator you will get the battery light come on, on the dash. When you replace it with another Alternator problem will be solve on the transmission codes. Good luck and hope this help