I took my 1985 380SE (with 220KW 560 engine on LPG) into the Authorised Benz garage for brake pads change and handbrake adjustment. After that the handbrake was no better than before and only functioned on one wheel.
A second visit resulted in the handbrake light to completly stop working and the handbrake to work a little better overall but not skidding on both wheels (so no handbrake turns ).
A THIRD visit finally resulting in a very strong working handbrake but with the light only working when the handbrake is yanked out to the 3rd notch. it doesnt come on at all on the 1st 2 and I normally only use the 1st one cause its too hard to pull out further all the time. I had a lengthly conversation with the service manger about it, after much beating around the bush, he finally admitted that the light should come on whenever the handbrake is on, no matter what notch it is set on and there was nothing he could do about it except a costly brake linings or somthing replacement.
I never forget the handbrake but I know when my daft freinds or mother use the car, they'll go driving around with the handbrake on, wont realise it cause theres no warning light and complain about the sluggish peformance!

However I pleased to find, that when I pulled the handbrake on while doing a U turn, that the rear end whipped around in a cloud of blue smoke and I was easily able to cut the usual turning circle in 1/2.

But overall, a total of 12 days and three visits to adjust the handbrake and now the light doesnt come on properly! GRRR!

 

sometimes they just can't fix it the right way even how easy it is.

i think the function principle is too simple to understand.