2011 Ram 2500 and Compustar CM2400

Hi All,

I am new here and have been reading through the awesome information that is contained on this site. It is great to know about this place but I am hoping y’all can help me out. I have a 2011 Ram 2500 SLT 6.7 Cummins with power locks and no FOB. I am trying to wire up aftermarket keyless entry in it and am having issues.

I have a Compustar 697A one way system with a CM2400 module. All I want this for is keyless lock and unlock. I don’t want to have the alarm, shock sensor, engine lock relay, etc wired up.

I believe I have found all the correct wires that I need for wiring this thing up but I can’t seem to get the doors to lock and unlock with the remote. I am using a DM600 polarity inverter to connect to the unlock and lock wires at driver side lock panel. I can tell the remote is communicating properly with the module because the status led is blinking when I click to lock/unlock.

Can someone tell me what wires I have to have wires up for this to work? Right now I have constant, ignition, ground, lock, and unlock wires hooked up. Do I need any trigger wires grounded or connected?

Or is it an issue with the truck itself…do I have to have a security bypass module in order for the keyless to work on the locks of this truck?

Thanks for any help and I greatly appreciate any info. I’m kind of stuck and would like to be able to button this project up.

Exactly what connections are you making? The wiring info I've found uses either a bypass/interface module or the passenger door lock switch multiplex wire which is grounded through a 330 ohm or 100 ohm resistor for Lock and Unlock. Not sure what you have the DM600 doing or why you thought it was needed.

For the door lock and unlock wires from the module, I tapped into the driver kick panel tan/white and tan/lt green wires. I thought I needed to reverse polarity in order for them to work hence using the DM600.

Those are the driver's door lock motor wires. Using them requires a 5-wire reverse polarity connection setup that is capable of high amperage. The DM600 is not that setup, it doesn't do 5-wire reverse polarity and it only supports 600mA of current for what it does do (simple polarity inverter). Tapping the lock motor wires would require doing both the driver's door and the passenger door if you want to unlock/lock more than just the driver's door with the keyless system. I suggest either an interface module or using the passenger door lock switch multiplex wire. A 5-wire reverse polarity setup is not ideal in this application - it requires the most wiring and work.

P.S. It's not much more work, than what you have already done, to wire in the alarm. All that's missing is the door trigger, hood pin (optional), and plugging in whatever sensors you have with the system.

Ok, so you’re saying it’s better to use the passenger multiplex wire which is Violet/Light Green if I remember correctly and wire up a relay and resistor for lock and another relay and resistor for unlock on the multiplex wire. I have found a couple diagrams that are showing me how to wire the relays if this is the correct way. How do I know what resistor values to use?

I really appreciate the advice and please excuse my ignorance.

Yes. You may be able to do it without relays - diode isolate if you don't use relays, a single diode between the vehicle and the resistors/module with the band towards the resistors/module is sufficient. The resistor values comes from wiring info, 330 ohm for lock, 100 ohm for unlock per https://www.the12volt.com/installbay/forum_posts.asp?tid=144266.

Addendum: In lieu of using two relays, you can also use a DEI 451M. It's essentially two relays in a single package. It may be a better option as opposed to buying two relays if you don't already have relays.

Thanks for the help guys. I think you have pointed me in the right direction now. I will give this another go when I get the chance. You wouldn’t happen to know where to buy resistors locally somewhere would you? I do have a couple relays that I can use.

don't need relays, compustar's lock / unlock output are strong enough to just use resistors on. Any eletronic shops near you? like old Radio shacks?

Thanks again for the advice. I can report back and say that everything is wired up and working to perfection.