viper 791xv constant +12v on unlock wire

Ok, I went through all the topics, and haven't found this one yet. I installed my 791XV a few months ago, and the ignition lock and unlock are both turned on. Today I started it and the doors locked as usual, but when I hit unlock, the relays were bangin each other back and forth, and then the actual door switch for unlock would not work and the locks were on. After pulling the wires, I found that the blue (+lock/-unlock) wire shows a constant +12v all the time. When I pull the wire everything is fine again, the door switch works both ways, and it will unlock with the alarm. As soon as I connect the wire again the doors lock and stay that way. Has anyone else had this problem? It's a 96 Jeep Cherokee. Thanks.Do it right the first time

Actually I did not use any added relays, I tapped right into the stock wiring. I talked to another installer today that said the same thing, it could be a bad brain. I've never had any problems like this before which is why I doubt that is the problem, I will have to triple check it again.    I live in upstate NY and the snow is out of control, so the wife's Honda is taking up the precious garage space right now .Do it right the first time

It was my understanding that you didn't NEED to add relays if you tap into the wire before the stock relay, I mean the vehicle does have a lock and unlock relay, that's how it works isn't it? I'm also sure that the wires are right. Sooo... why does the alarm's wire constantly show +12v?Do it right the first time

KarTuneMan wrote: Yes you need relays. How you got it to work as long as you did is amazing. You DO have the correct wires on the Jeep? Lock ORANGE / purple. Unlock pink/purple.   POS(+) pulse.

DEI's own lock wiring instructions say you don't need to use relays on these types of lock systems. In fact, that's the only reason for having both (+) and (-) lock outputs (which the 791XV does): so that they can control positive and negative locking systems without relays. Of course, you have to make sure you don't mistake a reversing polarity lock system for a positive pulse system. It sounds like the alarm unit is defective.

Well, I removed everything for the alarm except for the power supply and the receiver ant. and checked again, still +12 on the lock wire. Seeing how I just bought the alarm around Christmas, and we all know DEI's policy on installing yourself, I used the factory re-arm to power a relay for the locks. Working fairly well except for the fact that I can't use the 3.5 sec pulse(the locks are sticky when cold). If anyone knows where I can come across a good priced replacement please let me konw. Thanks again.Do it right the first time

Make sure that you have a good ground on the unit.  A bad ground or no ground can cause the unit to do things like that.Where theres is a wire there's a way.