Need help with Wiring

[FirstTimeBoat]

I just bought a 93 90tlrr 90 hp yamaha for my boston whaler. However it didn't come with the controls. So I bought a set off kijiji. I am trying to figure out where all the extra cables go. The 10 pin connects and the controls connect to that. Where I am getting confused is, I have an analogue tach with 3 lights on the bottom for oil. It's got a 3 pin plug coming off it. I figure this plugs into a control unit that came with it. What I can't figure out is where the 4 pin and 2 pin that come out of the control unit goto? What exactly is the control unit for? the 4 pin has a green wire, a green with red stripe, a yellow and a yellow with red stripe. The 2 pin has a green and a green and redstrip. Can anyone point me in the right direction here. I have a factory manual, but this box isn't it in. The manual diagram has the LCD tach.

 

[ClassicAQ]

Unless your analog tach is equipped with low oil and high temp alarms, and it's compatible with yamaha, I suggest not using it. A yamaha multifunctional tach gauge allows you to visualize alarms when activated. New ones aren't cheap, but used ones are. Otherwise, if you choose to stick to your analog you'll have to reply back with what yamaha control you've installed...binnacle, side mount, 703, 704, etc. Then post pics of the back of analog gauge, along with what connections you're having issues with. Or like I mentioned, toss the analog and invest in a modern tach.

 

[FirstTimeBoat]

The Tach is an OEM yamaha tach. I'm just wondering what the " Control Unit " box with 9 wires coming out of it does. it seems to plug into the tach and into a 4 pin harness. and then into a 2 pin harness. I m just wondering if this "Control Unit" is for the analog gauge or not.

 

[ClassicAQ]

No Title

I'm also wondering, but like I mentioned in my previous, post pictures. I have no idea what wires you are calling "control unit".

This picture is a wiring schematic for tach, speed, fuel. The throttle control has one main harness connection and pigtails that connect to the corresponding colored tach harness pigtails. The tach itself has one harness with two 4 pin snap in harness connections. Tach pigtails connect to the corresponding colored pigtails of tach harness.

 

[99yam40]

you still have not said what control you bought.

My 703 has some wires that let you add a remote T&T switch and has wires for a tach coming out of it

 

[FirstTimeBoat]

No Title

This is the control unit

 

[FirstTimeBoat]

it is a 704 top mount

 

[ClassicAQ]

No Title

This is the control unit

That picture you posted is of a oil tank relay assembly. See schematic, #54. Problem is, this relay assembly is not a part for your '93 90TLRR. It's associated with a '93 P50TLRR. This website doesn't have your engines oil pump system schematic. So to see it, google yamaha outboard parts and use their website.

Maybe there is a way to hook it all up and make it work. Though you're setting yourself up for future problems cutting this relay assembly into your control, on top of using an analog tach with no alarm indicators...IMO

 

[FirstTimeBoat]

Any Chance you have a wiring diagram for that motor? To me it looks like it will light up the red yellow and green lights on the tach I have.