Originally Posted by Mr.Oz
What did you do for the remote door locks?
I installed an AutoLoc KL550 5-channel remote locking system. I sourced it from Summit Racing, their main store is 15 minutes from me here in NE Ohio. Cost when I did it was about $80.00, it is up a little now on Summit's website here: http://www.summitracing.com/parts/hfm-kl550
Here is a direct link to the AutoLoc too: 5 Function Keyless Entry with Birt « autoloc.com
I have also attached a .pdf of the KL550 instructions.
On our Freightliners we have to use the "Reverse Polarity Locking" part of the instructions. You must make several connections on the lock wires, I did it right behind the dash switch. I cut the two appropriate lock wires and installed a pair of male/female bullet connectors. All connections actually soldered (not just crimped) and covered with heat shrink to ensure no problems down the (bumpy) road. I am very particular that way! Using the bullet connectors will allow me (should I ever want or need) to remove the lock system and plug the two original Freightliners wire back together, restoring things to bone-stock conditions. The connections (male/female) are oriented such that I cannot hook them up incorrectly.
You also have to supply +12-volt continuous power and a ground to the lock module, I tapped into the dash power point to connect those wires. I also ran the appropriate wire from the lock module to the headlight switch. The lock module creates a momentary "ground" in that lighting wire when the remotes are operated in the "lock" or "unlock" modes. This is to flash the running lights so you get an external visual indication of locking/unlocking. As it happens, our Freightliner light switch actually "grounds" the correct wire or wires to cause the Body Control Module (BCM) to turn the lights on. You do not need the lighting relay pictured in the KL550 instructions since we have a "grounding" trigger for our lights. So it works perfectly with the KL550, it pulses the ground to cause the marker lights to all flash. As I remember it was a brown wire at the headlight switch, but probing the wires and creating a ground will quickly lead you to the correct wire. One thing about the Freightliner BCM. After a while it seems to "go to sleep". While the locks themselves lock and unlock with every push, sometimes the lights don't flash with the first push. But when you hit it again they then flash appropriately after that wake-up. And the dash lock switch continues to function just as before for locking or unlocking from inside the cab.
I did not hook up the ignition interlock function, I figure if someone wanted to steal my MH that would not slow anyone down too much. And I did not want any failure there to prevent the unit from starting. If the locks fail I still always have the key!
After everything was connected to/from the module, which is very compact, was wire-tied to other wiring behind the dash just behind the lock switch itself after testing the installation. Then button the dash back up.
All-in-all it was an easy install, much more so than my last Ford E-450 where I had to contort myself to get into the kick panel to find the correct wires. And it is so convenient now at fuel stops and such to just to bail out and lock the doors; then unlock them as I approach.