I recently picked up an 08 F90 motor and put it on my boat. I used a 704 control and the separate Yamaha key switch. I also used a new wiring harness from the motor to these controls. I already had an existing 7000 rpm Yamaha Tach on the boat and plugged the yellow, black, and green wires from the tach to the harness. The tach works perfectly, but it has a temp light, and an oil light that are not currently hooked up. From the internet the tach may be a 6Y5-83540-20, but it may well not be also. I has one square connector with only 2 slots wired in and a free wire.

Is there any way I can hook these lights up to the new motor? The Temp light has a Green wire with red bands, and a yellow wire with red bands running to it. The oil wire has a red wire with blue bands and a yellow wire with red bands running to it.

The harness has a double yellow wire that feeds into a plug that is not currently used( switched power?) and a blue wire with a male connector (lighting?) that is currently unplugged in the lower part of the harness.

Above that there is a blue wire female connector that looks like it should plug into the lower blue wire. There is also a red wire female connector ( 12V power?) that is unplugged and capped earlier in the harness.

Besides the yellow wires these do not look like they would hook up to the warning lights. Is there a way to activate these lights? If I pull of the safety lanyard and crank the motor the warning buzzer sounds. Is this enough to protect the motor? I would rather not buy a new tach if I can help it. Thanks for any help.