Leaderboard

After seeing the code list, my thoughts are now that you're either going to be dealing with a bad sensor somewhere on the 5 volt reference B side possibly shorting out internally and taking down everything else, a chafed wire or corroded connector somewhere.....or even a failed PCM. I would ignore the harsh shifting and random no-start at this time, since those are likely just symptoms of the overall issue. 5 volt sensors generally work based on a voltage output to represent a particular value. Take your range sensor. It would receive a 5 volt signal, and would output a different voltage to represent PRND321. If the 5 volt signal going into the sensor is being pulled down slightly and randomly by something else, the output voltage will change, and the PCM can interpret those changes as different reported shifter positions. If the vehicle is off and its reporting something other than park or neutral....it won't start. It may also begin shifting funny as it no longer knows which position the shifter is in. If it were me...I'd be starting my troubleshooting on that 5 volt reference branch first.