Door Locks 92 caddy deville

Ran into a fun problem the other day.  Put in a Viper 160xvr into a 1992 caddy DeVille.  All tech info said that the door lock/ unlock wires were Light blue/Black and were located low in either kick.  There were positive so i used the DEI 451M.  Light blue tested fine and locked the door.  Ever black in both kicks tested to rest at ground and never went to 12v's.  Now for the fun part.  The only wire that went to 12v's in either kick was a tan 16 guage(unlock motor wire).  So i cut it thinking i could wire it like a 5 wire system.  The problem is that both sides rest at ground.  So i had to reconect it.  next i went into the door,  right at the switch.  You guessed it, black and light blue.  Both went to 12v's on lock and unlock, but rested at ground.  So if you send 12v's to a wire resting at ground, guess what blown fuse.  Has anyone ran into this problem before?  what can i do?  I called directechs (have an account) and they didn't have any advice.  PLEASE HELP!!Bknight187

First Class MECP Installer

pop the switch out and verify wire colors and function at the switch.... i just did a 92 Deville this week and the black  wire was dead... when i metered it at the switch it was still dead (intermittent switch) so i sprayed a little Super PPE (Anti-oxident spray) into the switch, worked it as bit and then retested and all was good, then when i went back and tested i found the right black wire..... BTW, a lot of these MY caddied the wires come in from the boot and run up, not down into the KP... you may have to grab them at the boot, not the KP.....  Kevin Gerry

Certified Electronics Technician

MECP First Class Installer

Owner/Installer

Classic Car Audio

since 1979

I poped the switch and both wires test 12v"s on lock and unlock(black and light blue) the problem is that they rest at ground and i can't send 12v's to a ground wire.  I checked at both switch's.  Bknight187

First Class MECP Installer

none of the caddys that were + i've done rested at ground.... and i just did an 86 Deville this morning that was + for locks and i wired it up directly to the Clifford i put in, without even using the 451M......Kevin Gerry

Certified Electronics Technician

MECP First Class Installer

Owner/Installer

Classic Car Audio

since 1979

Usually those wires are found low in the kick.  If I remember correctly, there were about 6 black wires all of the same gauge.  It ended up being one of them.