200 optimax tach not working

[rcook72]

Bought a 02 nitro with 02 optimax. The I am trying to figure out why the tachometer isnt working? With the power switch on when I turn the key it jumps and the light works but it doesnt give me a reading. Throught the wiring harness it goes from water pressure guage which also doesnt work, to the trim that does work, the tach that doesnt work, to the voltmeter that does work,to the gas guage that works. Any Ideas? Checked all the connections they are solid. I had the hours pulled on it before i bought it, is there anything they would have unplugged to hook it up to their computer, and not reconnected accidently?

[boatfixer]

Are you having any battery charging issues that you are aware of? When you increase the RPM's, you should see the voltage rise to 14.2-14.6 or so. The tach gets its signal from the rectifier which could be bad or the gray wire (for the tach) could have come loose. I'm not particularly sure where the rectifier is on the opti, but it will have 2 yellows coming from under the flywheel and a red and gray leaving it. Check the bullet connecters.

Because the needle jumps when you turn the key, it's not a power supply problem, rather it's a signal problem or the tach is simply bad.

[rcook72]

THX, That gives me a point to start looking for a loose connection. The voltmeter does go up with my RPM's