DionR
Well-Known Member
Gist of the question: can the VTSS function of an OBD2 PCM be put to use in a Magnum swap?
I’m working on doing an OBD2 swap into my Duster and so far I have a PCM from a 2000 Ram 1500 with a 5.2/MT and an OBD2 harness of unknown vintage.
After I acquired the PCM, I started looking at wiring diagrams and pinouts for a 2001 Ram 1500 (been unable to find a FSM for a 2000 so far) and started reading up on the security features that might be present in the PCM.
What I’ve discovered so far is that a 2001 Ram 1500 does not have the option for a special key (SKIM), but it does have an option for a security system (VTSS) that would cause the motor not to run. Based on the FSM, the VTSS system is part of the highline or premium Central Timing Module (CTM) and communicates with the PCM via the Chrysler Collision Detection (CCD) data bus network. Not all Ram 1500's have a CTM with VTSS, and it sounds like not all CTM’s with VTSS have the no-run feature enabled, but once a PCM has seen the no-run feature of the VTSS, the PCM cannot have it turned off (disconnecting the CTM does not disable it).
I’ve talked to a tuner about this and he said he has been able to tune it out, so I’m not really worried about my PCM and if it has the VTSS no-run feature activated. But it did get me to thinking about maybe using it to my advantage.
Just a little bit of back-story; I knew a local guy that was followed home from the race track and had his Demon stolen right after he parked it in his garage and was never recovered. Due to this, I started looking into securing my Duster and discovered that our old A-Bodies are pretty easy to hot-wire. I’ve since made plans and purchased a bunch of stuff to create what I hoped was enough security to discourage someone from trying to steal my car. Nothing is perfect, but mine kind of relies on a siren and some trickery and with time and a little knowledge it would be very easy to defeat.
The option of instead adding a CTM with VTSS and the no-run feature to the car seems very intriguing to me. It could go so far as honking the horn and flashing the lights if wired in correctly, but would more importantly cause the PCM to refuse to run the motor, regardless of what wires are cut/splice and/or what was unplugged. Short of someone bringing a different PCM and unplugging the CTM, not sure there is an easy way for someone to defeat this (short of a rollback). I understand that there are always ways of stealing a car and nothing is perfect, but sure seems to have some advantages over just a simple Viper car alarm where cutting a couple of wires would kill the siren and at worst a jumper to wire around the kill relay.
Best I can tell, at a minimum the CTM needs to have at least a matching key fob or the door lock switches (not the power lock switch, one that is turned with the key in the door) to arm/disarm the VTSS. Then it needs to be wired into the door pillar switches, and the 2 wire CCD bus connected between the CTM and PCM. With the VTSS armed, the motor wouldn't run and the car would be difficult to steal.
What I’m not certain of is if this is all it needs. I know the CTM is on the CCD bus with the airbag module, ABS module, overhead console (when equipped??), PCM and radio, so will the VTSS function if the only other thing on the bus is the PCM? Does it need to see the ABS module and radio, and if it doesn’t, the VTSS doesn’t give the go ahead to run? Anyone know more?
I know the default method is to rip all of this stuff out and flash the PCM to remove the security, but what if we could add it in with just a couple extra wires and such?
On a side note, pretty sure the CTM would also unlock the doors if they were power locks and you used a fob. It might even be that the PCM would tell the CTM to lock the doors when a certain speed was reached.
In my mind, it doesn’t seem like a huge task to add the CTM and make it work, but it is often the stuff I don’t know that is the issue, and I realize there is a huge amount of info that I might be missing.
Thoughts?
I’m working on doing an OBD2 swap into my Duster and so far I have a PCM from a 2000 Ram 1500 with a 5.2/MT and an OBD2 harness of unknown vintage.
After I acquired the PCM, I started looking at wiring diagrams and pinouts for a 2001 Ram 1500 (been unable to find a FSM for a 2000 so far) and started reading up on the security features that might be present in the PCM.
What I’ve discovered so far is that a 2001 Ram 1500 does not have the option for a special key (SKIM), but it does have an option for a security system (VTSS) that would cause the motor not to run. Based on the FSM, the VTSS system is part of the highline or premium Central Timing Module (CTM) and communicates with the PCM via the Chrysler Collision Detection (CCD) data bus network. Not all Ram 1500's have a CTM with VTSS, and it sounds like not all CTM’s with VTSS have the no-run feature enabled, but once a PCM has seen the no-run feature of the VTSS, the PCM cannot have it turned off (disconnecting the CTM does not disable it).
I’ve talked to a tuner about this and he said he has been able to tune it out, so I’m not really worried about my PCM and if it has the VTSS no-run feature activated. But it did get me to thinking about maybe using it to my advantage.
Just a little bit of back-story; I knew a local guy that was followed home from the race track and had his Demon stolen right after he parked it in his garage and was never recovered. Due to this, I started looking into securing my Duster and discovered that our old A-Bodies are pretty easy to hot-wire. I’ve since made plans and purchased a bunch of stuff to create what I hoped was enough security to discourage someone from trying to steal my car. Nothing is perfect, but mine kind of relies on a siren and some trickery and with time and a little knowledge it would be very easy to defeat.
The option of instead adding a CTM with VTSS and the no-run feature to the car seems very intriguing to me. It could go so far as honking the horn and flashing the lights if wired in correctly, but would more importantly cause the PCM to refuse to run the motor, regardless of what wires are cut/splice and/or what was unplugged. Short of someone bringing a different PCM and unplugging the CTM, not sure there is an easy way for someone to defeat this (short of a rollback). I understand that there are always ways of stealing a car and nothing is perfect, but sure seems to have some advantages over just a simple Viper car alarm where cutting a couple of wires would kill the siren and at worst a jumper to wire around the kill relay.
Best I can tell, at a minimum the CTM needs to have at least a matching key fob or the door lock switches (not the power lock switch, one that is turned with the key in the door) to arm/disarm the VTSS. Then it needs to be wired into the door pillar switches, and the 2 wire CCD bus connected between the CTM and PCM. With the VTSS armed, the motor wouldn't run and the car would be difficult to steal.
What I’m not certain of is if this is all it needs. I know the CTM is on the CCD bus with the airbag module, ABS module, overhead console (when equipped??), PCM and radio, so will the VTSS function if the only other thing on the bus is the PCM? Does it need to see the ABS module and radio, and if it doesn’t, the VTSS doesn’t give the go ahead to run? Anyone know more?
I know the default method is to rip all of this stuff out and flash the PCM to remove the security, but what if we could add it in with just a couple extra wires and such?
On a side note, pretty sure the CTM would also unlock the doors if they were power locks and you used a fob. It might even be that the PCM would tell the CTM to lock the doors when a certain speed was reached.
In my mind, it doesn’t seem like a huge task to add the CTM and make it work, but it is often the stuff I don’t know that is the issue, and I realize there is a huge amount of info that I might be missing.
Thoughts?
