I cut the wires on my trailer lights while they were plugged into the truck. Now my truck won't start and does all kinds of weird electrical things. Is there a reset, or something? Is the computer damaged? Am i in BIG trouble?

 

Can't imagine that there would be a cause for the trailer light circuit to effect the ECM. The light circuit is protected by a fuse and that should have protected the rest of the electrical system from you shorting it out with the wire cutters. Might start checking fuses ( don't forhet the ones under the hood)

 

Thanks Pestco1. I'll try that.
When I first open the door after I've left it for a while, there are no dome lights and a lot of relays clicking. I can put the key in, turn it on, then off and it's like it resets. The dome lights will come on and everything seems fine. The brake lights work. If you turn on the headlights, it goes out. If you turn on the flashers, it goes out. If you try to start it, it goes out and everything goes dead except some relays clicking. If you just turn the key on when it is reset and try a turn signal, it goes out.

 

I think what you have done is activated the remote anti theft personality module or RAP module for short. This is tied into your lights. I'm not sure on the trucks wiring because I haven't receive my service manual yet, but on the Taurus it is in the backup light circuit with the transmission range sensor. Check the fuses and see the instructions for resetting the Rap module Maybe someone on here has the wiring diagram to tell you which fuse it is?

Hope this helps

 

I tried to reset the RAP module and/or the remote entry switches. It didn't help. Like I said I can get the problem to reset sometimes, but as soon as I turn the key to the on position again it all goes dead. I ohm checked all the fuses in the dash panel and the hood panel. All were good. Are there any other in-line fuses or othert locations for fuses?

 

I think what you need to do is unhook the battery terminals and let it sit for for a couple minutes, then hook the terminals back up. That will set the puter and rap module back to the factory default settings. Start the truck and see if it does? If so let it idle for a few minutes to calibrate the puter. Then try to reprogram the remotes.

When everything goes out like your saying it sounds like it is going into the anti-theft mode. You may have damage the module. Did you check to see if your backup lights are working?

When you cut the wires you didn't hook them back up wrong, did you?

 

I have disconnected the battery. A few times actually. It didn't help.
I cut the wires on my trailer because I was replacing them. After I realized the 4-wire flat was still plugged into the truck I removed it. When I went to start the truck is when I noticed the problem.
I don't know what else to try.
Should I leave the battery disconnected for a long period of time to see if it will reset? Maybe overnight?

 

Doug,
Like I said before I haven't received the service manual yet, so it's all a guessing game on my part.

The problem that you have with electronic componets is that they don't like to be back fed(polarity reversed) or spiked. By cutting into multiple wires you could have energized the ground wire and blown a diode or some other ic in one of the componets. This is why they tell you to disconnect the battery before doing any electrical repairs.

I know that the RAP on a taurus is connected into the backup light circuit along with the transmission range sensor. I'm guessing it is also in that circuit on the trucks

What did you have turned on in the truck when the wires were cut?

Did you look closely at the wires that you cut on the truck side of the harness to see what arced to what?

 

Good news. I checked the battery and it was about 11v. I jump started it and it worked. It wouldn't do that when I tried that before. I let it run for about 30 minutes and shut it off. Tried to restart it. Nothing. So I jumped it again and drove to the auto store, bought a new battery, put it in and it started right up. I haven't had a problem with it all day.
I finished installing lights on my trailer and tested them. I have turns and brakes but no tailights. Any ideas?
Thanks for your help.