If I already have the Viper 771xv alarm, with remote start. Can I just buy a Viper 5900 and swap out the brain, remote and pager and have it work?

Or do I have to re-wire everything?
Like is it plug and play, where the old connectors fit into the new one?

 

For the most part, yes, except I believe the main harness may not be the same. Just compare the harness to see if each colored wire is in the right pin location. If not, since the connections were made already, all you need to do is cut and soldered the same colored wires together.

Valet, LED, AUX harness, RS harness, Keyless, etc. is definitely the same.

 

So its not plug and play, but I will have to some soldering... Thats not bad. I am also assuming that I will have to run a new antenna, and led right?

 

Bump-

 

All your inputs and outputs still remain the same, it's just the main harness I would double check to see if it fits. See if all the pins lined up the same and have the same colored wire. Also, be sure to pull the fuse out on the main power wire (normally red) before you make any changes.

The LED you don't have to change out, it's only 2 wires that complete the circuit, however, you should change the antenna.

 

Ok thanks alot man