Date: Thu, 15 May 1997 01:16:05 -0500
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: John Gladu <jgladu@bcm.tmc.edu>
Subject: Re: 87 Westy needs new power locks
mcelveen@onramp.net (Katherine McElveen) wrote:
>Thanks! Symptoms have been several: first, when I gave it a good washing
>one day, the locks started going up and down, up and down! This went on
>for a couple of minutes until I pulled the fuse. Seems the water got in
>somehow. I checked the driver side lock and found a tear in the rubber
>accordian-type cover (above motor). Problem resolved on its own.
>
>Later, pushing the driver lock down did not automatically lock the
>passenger side, but if you pushed down the passenger side it DID lock the
>driver side.
>
>So for a while, I just locked using passenger side. The other day, I
>couldn't push either lock down manually or with the key.
I've got the lock from a '90 open in front of me right now.
It's a clever mechanism, but has a few entertaining failure paths...
Moisture can cause all kinds of havoc with the switching mechanisms, as you
discovered with your first failure.
Staring at mine, trying to figure out how it all works, it looks like your
second failure was caused by no contact being made by one of the linear
contact switches in the failed lock. It would still lock (manually), but
not send the electrons out to lock the rest of them. Working one of the
other locks *would* send current to the motor in the failed lock and make
it move, but it couldn't send out current itself. Its travel was still
regulated by the circular contact switch on the big gear.
(I really wish, now, that I had taken notes when I removed the big gear to
show me how it should be aligned to everything else during reassembly.)
On mine, the white wire sends the "everybody UNlock" current.
The beige wire sends the "everybody LOCK" current.
The red wire should be positive voltage (that is "switched" to the beige
ans white wires within the lock) and the brown wire is ground (earth).
The white and beige wires remain in constant contact with their respective
circular switch plates on the big gear - white on the inner and beige on
the outer. Only the ground is interrupted during rotation - 180 degrees
apart. During half of the rotation the ground is shorted to the LOCK side
and during the other half to the UNlock side.
The motor only turns in one direction, with half of the travel driving the
lock slider up and the other half pushing it down. What I'm having trouble
figuring out, just staring at it, is how the driver pin on the other side
of the big gear contacts the lock slider so that it "gets out of the way"
after it stops moving it one way or the other...
(...ten more minutes passes - staring and turning gears...)
Okay - your third failure is caused by the big gear not travelling quite
far enough around for the drive pin on the back of the gear to clear the
UNlock ramp on the lock slider. Because it isn't out of the way the slider
can't travel down at all. Because the slider can't travel down the linear
switch can't slide onto the LOCK contact (going to the beige wire), which
drives all of the locks down. *Why* it didn't travel far enough around is
beyond my powers of deduction. Most likely it's one of the contact pins
that touches the round switch plate on the big gear - it switched "off" too
soon. Don't know why...
If you were to connect the brown wire (the single connector in the
three-connector plug that isn't parallel to the others two) to ground and
the beige wire (looking at the three-connector plug, it's the one on the
left when the ground wire is on "top" and the two parallel wires are below)
to voltage, it should turn. If the contacts aren't completely messed up,
it should also *stop* turning at the "locked" position. It might even
recover from there. Try pulling the lock up on the other door. Does it
now work correctly? If it does, I'd say it was moisture in there again.
If it doesn't, then one of the contact points is broken or bent or the
gears are stripped out. If it chatters or whirrs when you provide power,
but nothing moves, it's stripped gears.
[Mine failed because the bushing on the worm-gear end of the motor wore out
and the worm gear no longer came close enough to its straight-cut
counterpart. (I've turned the motor over in the plastic housing, and it's
a snug fit again, for the moment - won't last though. I bought a new lock
mechanism, but it requires a new wiring harness between the lock and
(wherever) upstream, and I can't remember if I bought that part and lost it
or just forgot... *sigh*).]
My next task is to clean off all of the black sealant on the two halves of
the housing and then reseal it when putting it back together (to keep that
nasty moisture out). Either that or find that expensive piece of wiring
harness... ;-)
Good luck!
bcnu - Grungy (John Gladu) (Houston, TX) Opinions are just that
INTERNET: jgladu@bcm.tmc.edu VOICE: 713-997-1117
'60 dddPanel walk-thru (The Bozobus)-----resting - melting 1600dp----
'89 Vanagon GL----------------------------good!-----------------------
'90 Vanagon GL----------------------------good!-----------------------
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