tach on MC9

[jhaggerty]

Hi Folks,

The tachometer on my MC9 has never worked since I bought the bus  last year. I would like to get it working. The connections at the alternator seem to be alright. Is there someplace I should check for volts, current, continuity or something. The Tach does not light up or make any movement at all. Thanks,

Jim

[JackConrad]

If your tach is like mine, it ha 4 wires (terminals) on the back of the tach.  one from the R terminal on the alternator, one is ground, one is the light inside the tach and the other is the power supply (12 or 24 volt) switched by the master switch.  What brand is the tach?  Jack

[jhaggerty]

Hello Jack,

It is a Sun tach. I have the wiring digram from MCI, I just don't know what I should be testing.

Thanks,  Jim

[jhaggerty]

I have just checked the back of the tach. It has three wires. One is the illumination and there are a white and a black, each going to a terminal on the back. There is also a black wire that is not hooked up and is taped over the end.  The tachometer seems to be grounded through the case. Any ideas how to test this unit?

Jim

[Dallas]

Jim,
You may find some help from the manufacturer.

Here:

http://www.sunpro.com/user_manuals.php