So have I installed many alarms in my old cars but none with a BCM and searched the forums but I can't seem to find my answer.

Looking at the DEI diagram I found online it shows both Power lock (at door) and lock motor (at BCM but says 5 wire). Everywhere I read on this forum says to tap into the door. I was wondering what the difference in those were? Also what does it mean "5 wire"? Is this a positive pulse to activate the door lock motor? And positive to unlock? Looking at the wiring diagram on the FSM it looks like the BCM switchs polarity to lock and unlock.

Thanks for the help.

 

If you are doing a full alarm you will want to go in to the doors because inside the doors you will be able to tag the OEM alarm arm and OEM alarm disarm wires (they are the same wires as the door lock/unlock wires). You will also be able to control the windows with extended (-) pulses on the lock/arm wire and the unlock/disarm wire. Honestly the OEM arm wire isn't important, but since the OEM alarm arms if you use the key in the door it is a necessity to hook up the OEM disarm wire.

If you were doing just keyless you could five wire the door locks at the BCM. Five wiring involves cutting the OEM lock and unlock wires and running the wires through the Normally Closed contacts on a relay. The Normall open pin (pin 87) then gets connected to 12vdc. Since both door lock actuator wires rest at ground all you need to get them to lock (or unlock) is to remove the ground the wire rests at and replace it with 12vdc. Since the other side is already grounded it will complete the circuit and pulse the actuator. When you five wire the door locks at the BCM you need to make sure you wire the Pin 30 side of the relay to the ACTUATOR side of the cut wire. If you don't, you can send 12vdc directly back to the BCM control output that rests at ground. This typically won't permanently damage anything, but in most cases you'll be installing jumpers on the BCM circuit board where traces used to be.