W123 key switch sticking / stuck (solved)
 

Well my sticky key switch problems came to head over the weekend.
Took the 300d to work on Friday and returned home without incident.

Went to start the car to test something else I had been working on
and could not get the key to move.

I had replaced the tumbler a few months back in hopes that was the issue.
However, whenever the steering lock engaged it was always a “jiggle and dance”
with the steering wheel and the key to get it to turn.

This fact kept me from making a couple trips already this fall as it could
not be trusted.

I was fortunate It failed at home, the now the trick was to get it to
turn one more time so I could get the tumbler removed.

After about 30 minutes of “jiggle and dance” success!

I disconnected the battery and pulled the cluster, (I’ve got some pieces
rattling around in there I will have to address before reinstalling) and
after contorting myself to get under the dash was able to remove
the entire assembly.

Once the assembly was removed I could tell it was the steering-lock
retract that was causing the binding in the switch.

Generally considered a non-serviceable item I commenced with disassembly
(or destruction if you prefer). I noticed a small peened in door on the
opposite end of the steering lock. I used a small disposable screwdriver
to separate the opening enough to remove the door.

The small anti- theft pin on the steering lock is just pressed in as I
grabbed it with a pair of vice grips and pulled it free (wear safely glasses
and there is a spring in there that might shatter when you pull the pin)

Once inside there was a pin that I guess acted as a keeper for the
steering lock to the rotating part of the switch that includes the
tumbler, steering lock cam, vacuum shutoff valve cam, and finally
the electrical part of the switch.

Once I drilled out this soft metal keeper I was able to pull the
rotating part of the assembly out and drive out the steering lock pin.

I cleaned up the interior of the switch a bit with a small file and
to my surprise, the entire rotating assembly slid back in and
everything seemed to function perfectly. Very smooth no
extra mass to rotate, just the single axis from the tumbler
through the electrical switch.

I do not anticipate further issues with the switch assembly.

This is a destructive process and you will lose, all anti-theft
features with the exception of the tumbler face. You will
also lose the key in buzzer function but does not affect the headlight buzzer


I have yet to reinstall but plan to this week.

���� Good job done ����

Reinstalled the key switch last night

The loose parts in the cluster were the ODO trip reset arms and pieces laying loose

Took a while but I figured out how to connect them so I have a working trip meter now.

No more steering lock but I'll grab a brake / steering wheel lock from ebay if I ever use public
parking in a big city. (fat chance)

Now I can travel without worry about getting stuck after stopping for fuel
or a bite to eat.

I do have to pull my cluster again as one of the illumination lights is not working
but with a 79 300D there is always a little work that needs to be done