Adjusting "soft top closed switches"
Jeff,
Those shops with Star Diagnosis would eventually point at the front locks - less experienced shops might even suggest to get a new controller. Almost any shop would tell you to replace the front locks, because they don't know about the ultimately simple adjustment procedure below.
Fritha78 was referring to a thread that was just posted yesterday. The OP's problem was that the rear of the soft top wouldn't even close after a new soft top canvas was installed, and the root cause was the same.
The red light staying on and the chime going off once you start driving is a less severe version of the problem, and the chime only going off once you drive over a bump would be the version where the switches just start needing adjustment.
It is unusual that both micro switches need adjustment at the same time. Has any work been done to the front locks lately, where someone might have bumped the switches out of alignment, or did you replace the canvas or the weatherstripping above the windshield?
In any case, below is the procedure to adjust the front lock micro switches, mostly paraphrased from the thread that Fritha78 referenced:
Here is how to check which one of the front lock micro switches needs adjustment in your case, where the red light stays on after the top has closed all the way:
Put the soft top tool (6-mm Allen wrench) into the front lock on one side, through the hole in front of the visor. Turn the wrench such that it locks even farther, taking the play out of the lock. That direction is different on the opposite sides, by the way. It is counter-clockwise on the left side and clockwise on the right side. If the red light goes out, then you have found the lock that needs adjustment.
Try the same on the other side if necessary.
(You might get away with only adjusting the prongs on your soft top, following the instructions in
http://www.benzworld.org/forums/r129...djustment.html, but that would likely be only a temporary fix and eventually result in the chime going off every time you drive over a bump.)
Adjustment procedure:
Note that you need to re-install the windshield header panel before the top will operate on model years '95+. Also, be careful not to pull on the wires of the magnetic sensor that is mounted in the windshield header panel on model years '95+. See page 3 of
http://www.tophydraulicsinc.com/R129... Removal.pdf.
The micro switch on the front lock(s) gets pushed DOWN by a lever when the lock is OPEN. There is some reverse logic involved here, so take it slow and read very carefully.
As the lock receives the soft top in it and locks, the small lever that is pushing on the switch releases just enough for the switch to click open once the lock itself is in closed position. If the lever has been bumped or bent when the front locks were installed, or if the locks have developed play over the years, then oftentimes the lever is not pushing down far enough by the time the lock is in the final (resting) locked position. This resting position can be different from the locked position without the top being latched down by the lock.
In your case, you probably have to bend that lever up just a tiny bit (1 mm or 1/32 inch). This adjustment can be made without removing the lock. Remove the windshield header panel and adjust the lever above the micro switch until it barely touches the switch when the lock is closed. Note the play in the lock - you need to recreate the position the lock would be in if the soft top was closed and pulling up on the lock. This is shown in the third photo with the caption "Front lock in real life with the top pulling". Ideally, the boot of the switch will just start bulging when the lock is in the "real life closed position".
I hope this helps - please let us know what you find.
Klaus
Top Hydraulics | Rebuilt and Upgraded Convertible Top Cylinders, Pumps, Hydraulic Lines - Top Hydraulics, Inc
