96 B2500 power door lock failure

[Tommy2500]

Door locks always worked fine until this AM. Hit the remote switch - nothing- no click -nothing. Unlocked manually. Tried interior switches-
nothing. We've had over 11" rain locally in the last 4 days and the Van parks outside all day and night. Could this rain/humidity/deluge
be a factor in the failure? A short maybe somewhere? Does this system
have a circuit breaker or relay that is vulnerable to getting wet? Any ideas/thoughts/help appreciated. The Haynes Manual is woefully
inadequate, and I'm inexperienced in this type of lock system. Problems
continue almost monthly with this Van....I love it BUT I hate it... Thanks.

[alloro]

On my 2000 the fuse for the power locks is in the interior fuse panel at the end of the dash.

[Tommy2500]

Thanks Alloro. Found fuse. It's a 30 amp, encased in a metal jacket,
so couldn't tell if its blown. Pulled it, scraped contacts, stuck it back in
and then the lock switches went "crazy" - clicking off-on-off-on etc. on
both front doors but the lock posts didn't go up and down, they just sort
of "chattered" like they wanted to move. WTF? Pulled fuse, substituted
it with the 30 amp. identical fuse for power windows (which work fine).
Same result....crazy clicking and chattering. So left the fuse out now.
Guess I'm stuck with manual locks like I had in my '76 B250. Damn.
Any further ideas? Thanks.

[alloro]

That's not a fuse within the metal casing, it's an auto reseting circuit breaker.

What it sounds like to me is that you have a short in one of the switches. The short is causing the circuit breaker to trip, then of course it resets itself and power flows again. The process keeps repeating itself, which is the chattering you're hearing.

The reason I suspect the short is in a switch is because if the switch wasn't making some kind of contact, then no power would be getting to the actuators inside the doors at the lock mechanisms.

[Tommy2500]

Thanks, Alloro. So that metal encased unit is a circuit breaker - aha - that makes sense and so does your notion that a switch short is the probable fault. Also makes sense since of all our rain lately.... SO, a couple questions; 1) to access the door switch, must I remove the door panel or can I pry out the switch unit which also houses the window switches? 2) If I can pry it out, tool suggestions? ...Method? Where on the housing do I pry? 3) Disconnect the BATTERY NEG. beforehand?
4) Test switch with continuity tester? or just replace? or try to dry it out with my hair dryer first? 5) Any chance the problem might be in the remote unit? Thanks again for help. You are a great aid.

[alloro]

Originally Posted by Tommy2500

1) to access the door switch, must I remove the door panel or can I pry out the switch unit which also houses the window switches?

2) If I can pry it out, tool suggestions? ...Method? Where on the housing do I pry?

3) Disconnect the BATTERY NEG. beforehand?

4) Test switch with continuity tester? or just replace? or try to dry it out with my hair dryer first?

5) Any chance the problem might be in the remote unit?

1. I honestly don't know. I added power windows and lock in my van so I don't know how the factory ones come out.

2. If you're going to try prying, I would use a putty knife since they're thin and flexible.

3. Most definitely during the take everything apart phase. Once it's all apart and you know nothing is going to touch metal to short out, you can reconnect the battery for troubleshooting the circuits.

4. Yes I would test the switches first, just in case I've steered you wrong. I'd hate to see you buy something that you don't need. Drying it out would be a good first step.

5. By remote unit, do you mean an aftermarket keyless entry system? If so, disconnect the main plug to it and see if the door lock problem goes away and you'll have your answer.

[Tommy2500]

Sorry to have been so long b4 reply. No luck on locks. I understand that the switches change the polarity of the relay, which make the lock solenoids either go "up" to unlock or "down" to lock. Before the circuit breaker stops altogether, the solenoids keep trying to "unlock" (push UP the locks). I'm thinking relay, but I CAN'T FIND THE DARN THING!
Does anybody know where it's located on my 96 B2500? Thanks.

[alloro]

Originally Posted by Tommy2500

Does anybody know where it's located on my 96 B2500?

If you power up the circuit can you hear the relays click? If so, you can find them by listening.

[Tommy2500]

Never did either hear a clicking relay nor even find the darn thing. BUT.... the weather dried out around here for several days and, on a whim (tried everything else)
I stuck the circuit breaker back in the fuse panel. Lo and behold, the circuit breaker
didn't try to reset (clickety, click) nor did the lock actuator soleniods go crazy (click- clack-click). So I tried the lock switch on both drivers and passenger doors, AND
....A Miracle! Everything works perfectly. I guess something got too wet and wouldn't work. Guess I need to move to a drier climate or build a garage.....
Thanks for your help, alloro.