Tachometer, trip counter

My tachometer quit working before purchase. I would like to get it functioning, but haven't a clue.
The trip counter also quit- neither has ever operated for me.
It's a 1986 560 SL - is this common for the yr, model?
I needsome guidance here!Thanks, Loquitus

Im having the same problem, only mines worked but then just quit.

i'm sure you checked your fuses.. i hope someone with knowledge
in this area responds because this truly does suck!!!!!!!!!!!!1


good luck !