Why do my door locks stop working when I try to install a stereo in my 2000 dodge caravan?

SOURCE: key turns in manual door lock but doesn't unlock truck door

you need to remove the door panel....the linkage for the lock has come disconnected...it shouldnt be too hard to reconnect

SOURCE: 2002 Dodge Grand Caravan Driver Door Lock/Unlock Switch

sorry not sure the 12v prob will help this swtich works on 5v off 3v unlock 1v lock single wire lock/unlock logic signals
I found wiring diagrams at
http://www.dodge.com/bodybuilder/2004/docs/wd/rswd/tc.pdf
it is 2004 but use the wiring diagrams to test the wires
(most likely to fail where they flex)
because it is using logic gates disconnect the plug at each end of the wire you are testing or the damn thing will find a few diffrent ways to trick you.

SOURCE: Auto locks don't work.

Instead of pulling a fuse which will definately trip off another time, why not take it for reprogramming?

I recommend you get an expert in security locks to reprogramme the locks for your car.

Rate this please.

SOURCE: 2006 Dodge Caravan - ONE power door lock stopped working

i have replaced many sliding door lock actuators on these vehicles..dealer part..mostly on passenger side sliding door..also possible you have a broken wire in door track harness..follow wiring from door into what looks like a plastic chain in door track at door opening

SOURCE: 2004 Dodge Ram 1500 Quad Cab Drivers side power door lock broken

Sounds like the link rod to the latch are jammed in the locked position by something inside the door or it came off. Any way, you have to remove the door panel to get access to it.