Tach Signal

[Scott_68B]

Can anyone confirm for me that the DIS used in 2.8/3.1 MPFI applications puts out a 5 volt square wave signal on the tach wire?

Thanks!

-- Scott

[TurboGTU]

RE: Tach Signal

square wave? Well I'll scope it..but im sure it is. Why?

[Scott_68B]

I'm modifying my stock tach with a circuit board developed by the Sunbeam Tiger guys for our old current driven British car tachometers. It needs a signal in that form. I figured the signal from the GM DIS was a 5 volt square wave but just wanted to make sure.

Thanks for the response!

-- Scott

[sean88accord]

i think the tach signal is a 12volt signal. but it also depending on the module might also be a 5volt ttyl and putting a tach on it will make the module go crazy