Replacement Gauge Wiring

[contrktr]

I have a Yamaha 150TXR on my Champion 22' Bay. I purchased Yamaha Pro-Series II replacement gauges for the tach, fuel, water pressure and speedometer.

My problem is that on the stock Champion gauges for the tach and the fuel, they utilize molded plugs and the new gauges do not.

On the tach, my current 4-wire plug has a purple, blue, black and gray wire making up the plug whereas the new tach has five wires. The first group of wires is a yellow, black, and green and the second group has a black and a blue wire.

Similarly, the fuel gauge has two molded plugs with four wires each and the new fuel gauge has just 5 wires total.

These gauges are all analogue and are replacing analogue.

Does anyone have a wiring diagram so that I can cut the plugs off of the boat harness and hook up the new gauges correctly?

[boscoe99]

What do you intend to do about the warning lights within the Yamaha analog gauge? Not use them or ???

I suspect that if you got the Yam trim/oil harness that runs from the motor to the helm and the mini harness that runs from the key switch to the gauges you might not have to do much wire cutting at all. Hopefully it will be mostly plug and play.

Anyhoo, here is a typical analog gauge arrangement drawing for a post 2005 Yam motor.

[contrktr]

I have the warning lights at the bottom of the console which are hard to see anyway, so I was going to disconnect them and wire them to the gauge if possible.

[contrktr]

On the wiring schematic you posted, is the yellow a hot for the gauge? The speedometer and water pressure gauges were easy, as they just had a blue and a black wire, which I am assuming is for the back light. On my wiring harness there is no yellow or even a red. I do have a group of blue wires which all tie together (assuming this is power and ground for the back lights?) and I also have a group of purple wires that all tie in together. Do you know if these purples are hots also? And if they are, why are they separate from the blue bundles?

Specifically on the tach, I have the yellow, black and green wires from the mini harness, so that's not a problem, and the blue/black will be power and ground for the back light. I don't have a trim meter so the pink is not an issue, but I have a red, a yellow and a brown coming out of the tach for the warning lights. I am assuming the yellow is power since it spits off to each light and the red will go to the oil pressure wire and the brown will go to water temp wire.



On the fuel meter, the original Champion meter had two 4-wire molded plugs plugged into them. One plug was marked "trim" but there is no trim gauge. That plug had a purple, blue, black and red wire in it. The other plug had a blue, black, gray with white stripe and a black wire in it. The new gauge has a blue and black wire group (back light assuming again) and a yellow, black and a white wire. The black splits off into two separate black plugs. I assume these two blacks are grounds for the sensor and the meter, and all will tie into the rest of the ground system. That leaves a yellow and a white, so my question is if I cut the old plugs off, should I run the yellow to the blue (power?) and the white to the gray with white stripe? Or do I need to use some of the wires from the other plug, such as the purple or red?

[boscoe99]

Yellow is 12 volt "key on" positive power. I believe that Mercury use purple for their key on power.

Blue is 12 volt positive power for the internal lighting. Usually it is con*****ed by a switch. Or, it can be wired so that any time the key is on the lights will have power.

Black is for the constant ground.

The warning lights in the tachometer normally have 12 volt positive power applied to them any time the key is in the on position. The lamps are made to light up any time the ECU applies a ground to them via the 6Y5-83653-XX-00 trim/oil harness. If you simply use the appropriate trim/oil harness connected to the motor, and the mini harness from the control box, you will have all that you need. It should be plug and play.

[contrktr]

rple. I believe I have it all figured out except that the lamps are currently wired with spade connectors and there is not plug that matches the small plug on the new tach, so I will have to cut that off and splice. On the old fuel gauge, it had two molded plugs with 8 wires going into it. I have no idea of why but now with your help and the color coding standard chart I found on another site, I think I can rewire it.
Thanks for your help.

[boscoe99]

You are welcome. Glad to hear that it has been figured out.