PeachParts Mercedes-Benz Forum - View Single Post - Wacko-Tacho (tachometer issues)

mach4 · #21 09-26-2013, 01:48 PM

The thing I find most interesting is the fact that the problem only manifests with the turn signal and not the flashers. That is essentially the same circuit, so that doesn't make any sense. I'd suggest pouring over the wiring diagram and see if you can identify something in common with the turn signals and horn that is not associated with the flashers.

Actually, maybe we're looking at the wrong end of things. Maybe there is something wrong in the tach gauge itself - something that makes it hypersensitive to certain fluctuations in voltage or RF or something. Get a tach module at the JY and swap it in, or borrow one from another car and just test it.

Of course you could always swap in an intermediate plate from an '85 and use the '85 tach pickup and module...that's a whole lot of work though!