[V6-12v] Trouble with 10-Year-Old Trunk(Boot) Lid Lock

[Gary E. RAFE, Ph.D.]

We've been having some trouble with the trunk(boot) lid lock
on our 1995 90Q for some many months now -- turning the key from
horizontal (neutral) to "open" and back and to "lock" and back
always worked fine, but the lock tumbler would get stuck in the
vertical (really locked) position occasionally.
Kind words and a little cajoling would always bring it out of the
locked position so that the trunk(boot) could then be opened
by pressing the "cylinder" assembly, thereby unlatching the lid.

On Saturday, however, my words weren't kind enough, and the lock
turned from the vertical position to horizontal with an unusual
abruptness, followed by the central locking alarm going off when
the lid was unlatched & opened (while the doors were still locked).

When we got home, I pulled the rear lock assembly out of the lid,
disassembled it, and found the cast ring that's used to engage
two microswitches for the central locking system with a broken
follower "tab" (the tab extends toward the center of the ring
and follows the central tumbler shaft/cylinder of the lock assembly).

The salvage dealers with whom I spoke Monday morning were not
interested in selling me only the "lock assembly" out of a good lid
(hey, why not, you sell door handles separately, right?),
so I contacted the local dealer, & I now have a new replacement,
for only $92 + sales tax.

My question has to do with tumbler of the lock -- I'd really like
*not* to have to use the (new) key that comes with the new
replacement.

Ideally, I'd like to "reprogram" the tumbler of the replacement
lock to match the original tumbler.
Is that possible, and if so, how to do it?

It seems to me, also, that when I pull the tumbler out of the new
replacement, I should be able to simply re-insert the original
tumbler in its place.
The question arising here is what to do about the spring that sits
at the end of the tumber shaft/cylinder ?
When I had the original lock apart, everything went back together
fine (apart for the broken follower ring), except that the placement
of the spring under the plastic piece on the end of the lock
assembly is not obvious (to me, anyway).

Any insight dedicated list members might offer to this will
be appreciated greatly !

Cheers,
--
Gary E. RAFE, Ph.D.	<mailto:rafege at mail.com>