viper160xv

The 160XV is a remote start, what are you talking about ALARM?

And yes it's 12 volts, but do you mean positive or negative?

yea it is alarm with remote start. negative

What car?

toyota funcargo

Have you found your lock and unlock wires on the car, should be low current neg, AKA type "B" in the driver's kick panel. Test as following: Should be a loom coming from the door into either one or two white plugs. Take a Snap On test probe with an incandescent bulb (forget DMMs this is faster), place the croc clip on a good ground (steering column or a bolt in the kick panel) place the probe end into each terminal on those plugs, make sure the key isn't in the ignition and the door catch is turned (at rear of door). That should give you your lock and unlock wires. Also make sure your lock/unlocks from the 160 go to neg on lock and unlock.

yes i found the wires already