yessir, got reverse lites so maybe it's this sensor. I craweled under and saw what I think is that sensor. what would happen if I bridged it and put it direct ?
Its the only sensor on the trans on the driver side, right above the pan. Big black thing with a lever on it, connected to the shifter linkage. Also make sure that the plug is in there tight and make sure its clean.
Not quite sure what you mean my bridging it, but you can bypass it by jumping the starter solenoid on the fender. That will start the truck no matter what, but if the sensor is bad then it might/should shift weird. If you were to unhook or bypass the sensor then the truck shouldn't even be able to move, as the tranny won't know whats going on, and it still won't start with the key.
It might also need adjusted, seeing as it won't start but you have reverse lights, cause they are tied into this sensor. I've been troubleshooting problems on my new trans and had broken off the top of this sensor. Installed the new one and the truck would not start at all in any gear. Got to talking to the trans guy and he told me to make sure i had it lined up, which i didn't. Lined it up and now its starting fine. Its possible that its vibrated out of alignment, so this may or may not help you.
What you do is put the truck in neutral and set the parking brake. Crawl under and pop the shifter linkage off the lever, then take the lever off. The sensor slides over a rod, and it is a disc that rotates in the sensor. There is a groove on this little ring/disc, and one on the sensor itself. They have to be lined up perfectly in neutral for it to know what gear your in. To adjust that you loosen up the two small bolts and move the sensor around till their lined up, tighten em up, and put it back together.
Sounds complicated, but its really easy. Without having an actual scan tool that is about the only thing you can do to troubleshoot it. If its lined up perfectly already, then i'd say you have a bad sensor or bad connection. If its not lined up perfectly already, then this should help it.
Or it could always be somewhere else, and for whatever reason wiggling the shifter somehow let it start.