2005 monte carlo door locks

I am installing a Viper 791 in a 2005 Monte Carlo. I have everything hooked up and working minus the power door locks. According to the wiring diagram the ORANGE / black wire at the PCM controls the door locks. If a straight negative pulse is sent the doors are unlocked. If a negative pulse is sent through a 470ohm resistor, the doors are locked. I have the ORANGE / black wire t-tapped once and have both the unlock (straight -) and the lock (wired up with 470 ohm resistor) connected into the ORANGE / black wire. However, the doors will only unlock. They will lock when the unlock wire is disconnected so I know the resistor is wired correctly, but for some reason when both the lock and unlock wires are present only the unlock works. Any ideas on how to get this wired up? I looked through the examples on here and found a dodge caravan that required a negative pulse through a resistor for both unlock and lock and that appears to be wired up the same way as mine, only my setup isn't working. Thanks!

This is an LS model Monte Carlo. Forgot to add that to the above info.

Not real familiar with the Viper 791 but I see from the install guide that it does (-) / (+) pulses from the lock outputs...   Diodes might work or

Have you tried using relays as per the top diagram on this link ?   http://www.bulldogsecurity.com/diagrams/extrainfo/diagrams/14301_MONTE-CARLO_MONTE%20CARLO%201%20WIRE%20JBS%20UNITS.pdf

Soldering is fun!

Thanks, kreg, I'll give that a shot. What a pain in the ass...two relays! I bought the XK01 hoping that it would do door triggers, trunk release, PASSLOCK bypass and door unlock/lock all over the data bus...that didn't work looks like this is going to be a much more time consuming way.

The 791 with flip flop lock outputs won't have enough current to fire past the resistor. Use a DEI 451 module or a pair of relays (which gets rid of the need for diodes) Take the relay lock out put and wire in the resistor, then join to the unlock output then to the vehicle wire and by the way don't T tap, solder. Your probably losing half the current that way.

You can try this, usually works.  470 Ohm resistor on the lock wire (green)  and a diode on the (blue) unlock wire, band towards the 791module.  Then connect that to the Org/Blk wire.   Old trick for malibus, grand ams, ETC.

Mark, you will still need relays both sides, the 791 output isn't strong enough to overcome the resistance, in fact directwire for that car says use relays, I've had to on Euro VWs which use a similar mux system. Once you use relays you won't need any diodes.

I worked on an '04 Monte Carlo not long ago. It required 2 relays and a resistor for the lock.

OK.

Directwire says that "needs relays" for the Malibus, MonteCarlos...  etc.   and it works on them.  Maybe not the Org/Blk vehicles. 

Chris Luongo turned me onto that trick in the DEI froum way back, and I've used it many times.

Mark, much as I wouldn't argue with you and Chris, two of the Gods of this business there's an easy test to prove or disprove what I say:- If our original poster simply runs the two leads, one with the resistor and the plain lead back to ground one at sat time with either the driver's door shut or the lock catch thrown over it should work the locks. The poster then makes sure the 791 is putting out a neg each time. If so relays are required.