So I had the normal over drive switch wire go bad on me. I first soldered the wires back and then the od switch light just stays on. So I thought I botched the solder job and bought a new switch/handle. Just installed and same thing. Please help . Does something need to be reset? I disconnected the battery and that didn't help.???

 

Are we supposed to guess what you're working on?

 

My bad.. 2002 F250 4x4 v10.

 

There is nothing to reset. Most likely there is a wire still shorted to ground. There is an outside chance that the PCM is bad. Those are the only two ways this can happen.

 

So here is where I'm at. Truck starts and drives fine. The OD inhibit light is on upon start up and while driving. If I physically unplug the switch while driving it shifts into OD. Plug it back in and it shifts back to third. The new switch and the old switch both do the same thing. Still think bad PCM? It worked fine before the wires frayed..

 

I can't find any other shorts.. thank you for the reply

 

Have you unplugged the harness from the PCM and measured the OD OFF circuit for continuity to ground?

 

Today I checked all grounds. Checked it with the control module plugged in and unplugged. Not one tone on my meter. So check this out.. Not sure if you knew(sure you do) but you can remove the bezel on the end of your gear selector and the button inside can be unplugged and plugged back in. So like I said before the button light just stays on all the time and the truck will not shift into OD. So while driving if I remove the button it will shift into OD and all is well. Drives completely normal with the button removed hitting all four gears. Plug the button back in and it down shifts into 3rd. Now this is where it gets weird.. If I remove the button and plug it back in(less than a second) the light is on but it still shifts into OD. It drive like the button is removed. If I shut the truck off and re-start it it goes back to only shifting the three gears. Same thing if I remove it.. all four gears. Plug it back in after a couple seconds.. back to three gears. I'm wondering if the electronic switch in the trans got toasted or tripped out some how when the original wires were shorting.. I'll take whatever comments or suggestions. For now if I'm towing I'll just remove the button. Thanks for your response and comments.

 

New switch bad? Can you test continuity on the new switch?

Good luck!

 

Thanks for the suggestion but yes I tried the new switch.. old switch... even tried my buddy's switch from his f250. Same thing.. I wish I had access to a spare PCM.. As far as I can tell the button just closes the circuit momentarily sending a signal to the PCM.. I know the system is supposed to reset itself every time you start up. So the OD inhibit is off by default upon start up. Mine is on during start up. I'm hoping I'm not just a one off.. At least it manageable and I can live with it but if I ever want to sell the truck it's definitely ghetto

 

Thanks for the suggestion but yes I tried the new switch.. old switch... even tried my buddy's switch from his f250. Same thing.. I wish I had access to a spare PCM.. As far as I can tell the button just closes the circuit momentarily sending a signal to the PCM.. I know the system is supposed to reset itself every time you start up. So the OD inhibit is off by default upon start up. Mine is on during start up. I'm hoping I'm not just a one off.. At least it manageable and I can live with it but if I ever want to sell the truck it's definitely ghetto