Yamaha Outboard Gauge Wiring Diagram: Everything You Need To Know
It might be challenging to install a gauge package on a Yamaha board since the wiring is so intricate. However, after learning the color codes, you encounter a Yamaha outboard gauge wiring diagram and find yourself utterly baffled as to how to actually mount one.
In short, the tachometer is where all your wires go first and is considered the mother of all the gauges. From there, the wires are split to the fuel gauge, volt meter, and speedometer. Thus, the yellow power cable and the black ground wire are attached to the tachometer. Followed by the other gauges.
However, saying this is easier than done. To know what’s actually going on, a diagram isn’t enough rather, showing it in practice is way more effective. That’s what we are going to do here. So let’s get started.
Yamaha Outboard Gauge Wiring Function
Before we dig in deep, it’s vital to know which wire’s function is what. Thus, here’s a wiring color-function chart that will come in handy;
Function | Wiring Colors |
Battery Positive | Red |
Battery Negative | Black |
Temperature Light | Pink |
Warning Buzzer | Green/Red |
Tachometer | Green |
Start | Brown |
Kill | White |
Trim Sender | Pink/Black |
Key “On” power | Yellow |
Trim Up | Light Blue |
Trim Down | Light Green |
The Yamaha Outboard Gauge Wiring Diagram In Practice
In essence, the chart has shown you every colorful wire associated with a particular outboard. Now that you know which wiring color leads to what function in your Yamaha Outboard, let’s take a look at the diagram first;

Before we go into practice, you should have a volt meter, speedometer, fuel gauge, and, lastly, the tachometer in front of you now.
In this instance, we’re going to begin at the position of the gauge harness connection and work our way to the work we need to do on the gauges.
Before you start with the placements, begin with mere gauges and remember to create your own wiring harness so that every motor has a black ground that ties into the key switch or the gauge harness, which will be the black ground originating from there.
Placement
When it comes to the placement of the wirings, the tachometer is the brain of all connections. Every wiring is basically run to the tachometer from that harness and then to other meters.
Key ‘On’ Power- Yellow Wire
The positive terminal of the battery, which has a small blue jumper that will only power the light bulb in the gauge, is where the key ‘on’ power enters. Therefore, if you ever see a blue jumper wire, it’s usually only to backlight the gauge with light.
Thus a positive post here key ‘on’ power will power this gauge, and that will jump over to all of the other gauges.
For example, the power for the speedometer will jump over to my backlight; then, it will jump over to the voltmeter. As well as finally, it will jump over to the fuel gauge. We must tie our power in everywhere, and we usually just piggyback it in these gauges.
Ground- Black Wire
The ground wire should go in the middle post of the tachometer. From there, we leap from the ground to the speedometer, then from the ground to the volt piggybacking onto the fuel gauge. You must ground through both the key switch and the ship’s sending unit for the fuel gauge.
Why? since it has power ground and a sending unit from the tank. So bear in mind that there are two grounds on your fuel tank. One of which should never be touched by the electricity to the sending unit (the sending wire is marked with an “S”); if you do, the gauge may be damaged.
Tach- Green Wire
Last but not least, our green wire enters our tachometer and finishes there because it is a one-and-done. What it does is tell the system about the engine speed from the ship’s tachometer signal. Therefore, the only place where you would be needing a green wire to be installed is the tachometer gauge only.
Changes In A GPS Speedometer
Well, there are some changes that you would need to go through if you thought about upgrading your speedometer. For a manually driven speedometer, you will only come across positive and black terminals.
On the other hand, if you had a GPS model, all you would need for power would be a positive and ground. In addition, to backlight your speedometer, you would then need to connect a blue jumper wire to your speedometer.
Overall, the blue wire from the tachometer would need to be shared with a GPS speedometer.
Voltmeter and Fuel Gauge
The voltmeter is quite simple to comprehend. The positive post where the key “on” power enters will then jump a blue wire, backlighting the gauge. The fuel gauge is backlit by a light bulb that is located here, and our ground wires then leaped onto our ground post and latched onto it.
It has a ground-positive outgoing line, and the blue wire simply crosses over to power your lightbulbs. You can’t see it since it’s usually already grounded, but the light bulb has a ground that links in the gauge to our ground post. As a result, all you have to do is feed it with electricity.
Conclusion
To conclude, that was all you needed to know about the Yamaha outboard gauge wiring diagram in practice. Knowing the wire colors can help you tremendously in setting up the gauges in place. In short, it lets you know which terminal is suitable for the desired wire.
On the other hand, making up a wire harness is essential as it will be a mess if you don’t. Once you are ready, simply connect the harness to the tachometer and follow the diagram to attach it to the other gauges.
You Can Also Read:
was a great help bought used motor a they cut the plug ends off thanks