I am installing a remote starter in an 05 F150 with keyless entry. It's all done except for the wire that sends the signal to the remote starter to start. It requires a negative pulse that I am suposed to get from the door lock or unlock wire. I have those wires at the drivers kick panel but they don't do s*#t. I have been trying to figure this out for hours. I need to be able to use the factory transmitter to remote start the truck. It seems like the wires are real low amperage or something but I read nothing with my multimeter. What do I have to do to get those wires or any wire to give a good negative pulse when I hit the transmitter? This is killing me?
Thanks

 

You are going to have to find the door lock actuator wires. I think the left front is red/orange and pink/black.

Then get a testlight or voltmeter and see which one of these wires has 12 volts when you lock or unlock the door(I don't know which one you want to use). When you find that, then go buy a relay and hook the coil to this wire, and the other side to ground, so when you hit the key fob, the relay clicks.

Then hook your remote start wire to one of the relay contacts, and hook the other side of the relay contact to ground. This should give you a negative pulse.

 

Thanks man. I have a few relays around and was thinking about that last night. But while I am good at this kind of thing I am not that good. I figured there was a way to do what you said I just did not know how to do it. Now I do. Thanks. But I seem to have it working now (with the exception of the PATS system.) I hooked into the other wires like you said to do. They showed a ground and then a +12v pulse when the lock or unlock was hit. Even though it is a +12v pulse it works because when you hit the lock it goes to +12v briefly and then back to ground (or -negative). So there is one negative pulse. Hit the switch again and again it goes + but then right back to negative. That being the second pulse and the remote kicks in. But it turns right back off because I have the PATS hooked up or programmed wrong. Just need to figure that out and I should be good. Thanks again for your help.

 

A remote start / Keyless entry is the simplest avenue. The RS/KE can be programmed to utilize the OE remotes or just use the Supplied remotes,,,,,, or all 4 remotes.
The systems start at $80