Rewiring Gauge Cluster Ground Issues

[NateTheNewb]

So here's the wiring diagram that I have for my GS650E...

https://f9bc88ff-a-17412f65-s-sites.googlegroups.com/a/dslextreme.com/cbsaunders/images/1981GS650EX.Jpg?attachauth=ANoY7criY5uFcNFk2ioeyvYv2UqO-aNa2z6Mpfn6EyzGKrzXe1GxtG98xkDfw1TMezYL508pMtpJTVVIa9-W_m9tZUmmiH-373hcqeRwyS-vJjNuQULqeVh3u4mN3_QjX-Dd-0FC8cSohPX1UmE8yg7UedbfZidxYOknAgdGmPu4K05BK65LETBkgl-6WRCl1oBpbpDyQseFVjBXEkz19iou7CU1yDioQ78aORQ4yrEOqE559SvFEBk%3D&attredirects=0

...and I'm having trouble with the green and yellow ground from the oil warning light. It's directly wired to a ground down there somewhere, apparently, but it is not serving as a ground. I have attached my volt meter to a bolt on the negative and a live wire to get my reading, but when I move the ground to the open green and yellow it loses it's signal.

Also, the horizontal and vertical terminals shown coming from the bulbs show no consistency as to which one is the ground and which one should be live.

This is the product I'm installing...

http://www.dimecitycycles.com/vintage-cafe-racer-caferacer-bobber-brat-chopper-custom-motorcycle-electronic-parts-mini-black-face-led-speedo-speedometer-25-7032b.html

...The neutral indicator and the oil pressure light appear to share the same power wire (orange/green), so far as I've discovered, the ground for the neutral light (blue) works fine, but the wire in question does not, even though it appears to be the most direct ground connection that I have.

Help

[NateTheNewb]

Addendum

Solid black ground doesn't work either.

[NateTheNewb]

So I'm still talking to my self...but the yellow/green is obviously the power + wire connected to the switch which is then grounded, and the oil pressure and neutral indicators share power?

I'm lost, can someone give me a definitive idea as to what wires are + and which are - ? Kinda going crazy.

[Mekanix]

Your diagram says it all.

The oil pressure switch connects that wire to ground when there is no pressure. That's all, Its only switches that ground connection on or off.

Your oil light has a positive wire on it that is powered all the time when the key is on. But it only lights up when the oil pressure switch grounds out.

Your new gages should be wired to have the oil pressure and neutral lights getting power and to turn them on, you have to give them a ground from what ever sensor they are hooked up to.

I would think that all you have to do is give power to the gage how ever you want. Just use one of the orange/green wires that went to the oil pressure or neutral light.
Then connect the neutral wire to the one going into the gage and connect the oil pressure one to the gage. They should work just like that.

The neutral light should come on when its in neutral because your giving it a ground. It should be the same for your oil pressure light. Once it grounds out you should get a light. And it will always be grounded when the engine is not running.


All your interested in is the direct wire going to each of the sensors. You don't need to use the other wire that was going to the light for anything besides power.

If you want to be sure which wire is which on the oil pressure light or neutral light. Take the two lights out and turn the key on. Now, measure voltage from the battery Negative to each of the light bulb connections. One of them for each light will give you 12v and the other will give you 0. The one that gives you 0 is the wire that goes to the sensor.

FYI, If you just try to measure grounds your going to get confused. Because, If you tried to measure a ground and you went to the positive side of the light connections it would still act like it was grounded!! Know why? Well you have another light somewhere else that is causing it to seem like its grounding out. But its not, Its just giving you another path to ground.

Its easyer to check for voltage and be sure.



Help any ?

[NateTheNewb]

So than it sounds like I was correct the first time, the green/yellow is a ground, just an interrupted one, disconnected as the oil circulates? This makes it so the neutral light and oil light can share the same power, right?

If this is all true, than my oil switch must've started malfunctioning, because when I connect it the light doesn't ever come on, unless I use a different ground for the sake of testing, but I don't want my oil light on all the time.

So what about the solid black one, why no solid ground for that one I wonder, and yes, you've been helpful, if anything giving confidence to my theory

The gauges just come with postive and negative for each indicator bulb and led backlight, a total of eight. Pretty straight forward, it's really just the original grounds not working.

[Mekanix]

Start it up. It might just be that the pressure sensor is. sticking open and might work better once its cycled a few times.