90 HP Yahama Electrical Problems

" I have a 1999 90 hp Yamaha w

" I have a 1999 90 hp Yamaha with the Yamaha Tachometer. The motor runs fine, but the tach/trim indicator display is dead. Anyone with a schmetaic or some advice?

THANKS

jIM "

" A tachometer normally has on

" A tachometer normally has only four connections. 1) 12 volt power feed. 2) Ground. 3) tach signal. and 4)12 volt illumination feed. If the tach is illuminated with the instrument lights on, the ground connection is obviously good. If not, start by checking the bulb. If its ok, check the ground connection. If its ok, make sure the 12 volt power feed is present with the ignition key on. If not, find the open. Check the fuse if there is one. If 12 volts is present, the tach signal from the engine is missing or the instrument is defective. You can check continuity of the tach wire between the tach head and the engine with an ohm meter or test light. With the engine running you can also use a voltmeter to test for a signal at the instrument. If you have any reading at all, chances are the instrument is defective. Hope that helps. "