I am hoping someone has the solution to my problem.The door locks on mydaughter's 98 LX (without keyless entry) suddenly stopped working. I have checked the fuse under the dash and the fuse under the hood. I checked the switch in the driver's door and even removed that plug and used a jumper to see if the switch was bad. I called the parts dept. at the dealership and asked about a relay. He said there was no relay and that it was probably the main computer behind the passenger kickplate that is bad. This part is $95!! Does anyone else have any ideas what might be wrong. I don't want to spend that much money to fix this problem. Thanks

 

It's frightening what people at the dealership can sometimes say.

Start by troubleshooting the power lock control unit behind the driver's door trim:

 

Thanks Ron. I located the power lock control unit and ran all of the tests listed. I still can't get them to work. The only thing I haven't checked is all of the individual actuators that are in the doors. Any tips on removing these little buggers?

 

well to remove the little actuators youd need to pull the door latches.... i dont recomend that because if they went bad then their would at least be one that would work fine.LOL id say its the lock modual if it was power.....
probe the white/green wire for power with a light tester if theirs no power than its your fuses or maybe a broken wire running to the modual...

just try some junk yards for another lock modual.... i have one for my 94civic but they are probably different....

 

If you did all the rests in the pictures and no problems were found, then the control unit itself is bad. It's seems unlikely that all the lock actuators would fail at the same time.

 

I found a new control box today in a junkyard. I took it home and the door locks still don't work. I troubleshooted again and found that the black wire that is supposed to be grounded, is not. There is no continuity at all. Does anyone know where this wire is grounded? I ran a jumper to the black wire and then to a ground and tested the locks and they all worked correctly. Now I have another question...If I just ground a jumper wire and tap into the black wire that goes to the lock control box will this harm anything? Thanks

 

The wire is grounded through a floor wire harness attached at G551, which is behind the driver's kick panel:

 

Thanks Ron, that's just what I needed. Tell me something, if I can't find a problem with that ground wire (g551), would it hurt anything to just run my own dedicated ground wire and splice into the plug?
I just went out and checked and the wire is grounded and shows continuity from the ground bolt until it goes up into the door pillar. Inside of the door, though, it is dead. I guess the wire just broke inside of the loom somewhere.

 

Improvising a solid ground to the body frame should be fine.

 

Thanks for your help Ron. Now I've got to sell this other door lock controller on eBay