fuel gauge wiring

[Matchless]

yes you brit's have it correct, positive is "earth".

I worked for many years on electronic equipment that had the positive "earthed" or grounded as you folks call it. I even recall some motor cars that had positive to earth from way back, I think they were Italian.
We just used to call a positive line an "earth" for short and force of habit is hard to break. I have to constantly think "ground" is negative etc.
We are not Brits, but their influence left their mark!

hmm.. i have 4 wires light orange, black with yellow, yellow with black and a solid grey one. now, i ( probably foolishly ) assumed that the grey one was supposed to be grey and red/orange and ran that to the horn positive, the yellow/black black/yellow to the sending unit and the orange one to a bullet connector that was orange in the headlamp. when i disconnect the orange one, nothing happens...

Seuadr,
Usually the orange wire is the switched hot wire from the ignition switch and back to the fuses then the orange/red, orange/green and orange/white are fused in series with the main fuse via the ignition, the orange wire. Your fuel guage should get its 12 volt positive from the orange/green wire or orange wire to a voltage regulator in the gauge, which also has a negative ground. The full fault finding and diagram is available in the manual for the 850 or 1000 maybe others as well.
Keep well

[rustybronco]

We are not Brits, but their influence left their mark!

I was speaking of the brit's and their using the positive lead to ground and I guess it would apply to other country's as well. it was a positive comment, please take no offense.

Your fuel guage should get its 12 volt positive from the orange/green wire or orange wire to a voltage regulator in the gauge, which also has a negative ground.

that would explain the negative wire at the gauge.

[Matchless]

rusty,
No problem at all!! All meant in good fun!

[seuadr]

I worked for many years on electronic equipment that had the positive "earthed" or grounded as you folks call it. I even recall some motor cars that had positive to earth from way back, I think they were Italian.
We just used to call a positive line an "earth" for short and force of habit is hard to break. I have to constantly think "ground" is negative etc.
We are not Brits, but their influence left their mark!

Seuadr,
Usually the orange wire is the switched hot wire from the ignition switch and back to the fuses then the orange/red, orange/green and orange/white are fused in series with the main fuse via the ignition, the orange wire. Your fuel guage should get its 12 volt positive from the orange/green wire or orange wire to a voltage regulator in the gauge, which also has a negative ground. The full fault finding and diagram is available in the manual for the 850 or 1000 maybe others as well.
Keep well

Ah! i didn't realize there should be two hot wires. i think that is where i am running into trouble.. for whatever reason, the gauges i have are off a 550L and they only had 3 wires comming out of the fuel line, the black/yellow yellow/black and solid orange. the other must have origionally been hooked up somewhere internally. i'm going to have to take the back off and see if i can locate that third wire and run it from a known ignition on wire then. thanks!

[Matchless]

Seuadr,
Just before you do that and to make sure we are talking about the same thing here. At the guage there is one switched positive wire that feeds the regulator and should be internally wired to the gauge. Suzuki usually uses orange, so an orange wire should be coming out of the gauge and usually that one is the 'power' for the gauge. The built in regulator should have its own negative or ground wire at the gauge, usually black/white. Another black/yellow wire runs to the tank sender unit and is the wire that controls the gauge reading depending on the variable resitance read at the sender unit. The sender unit in the tank also has a 2nd black/white wire from where it gets the negative ground that is on the other end of the variable resistor in the sender unit.

To sum up:One side of the tank sender unit is connected to ground and the other side to the gauge, in between these is a variable resistor. On the gauge one side is connected to positive 12 volt and the other to the tank black/yellow. See it as a lamp with the resistor making it dimmer.

I am most likely over explaining and thus not making good sense or you may have a slightly different configuration.

[seuadr]

I am most likely over explaining and thus not making good sense or you may have a slightly different configuration.

no, you make perfect sense, we just have different setups.

my gauge has a black/white wire, a grey wire and an orange wire. my tank sending unit, on the other hand, has a black/yellow wire and a yellow/black wire. now acording to the wiring for my bike, the black/yellow and the yellow/black run to the gauge, but the gauge has black/yellow, orange and yellow/black. and orange. i hooked the orange to the orange from my bike, and the b/y and y/b to the corrosponding wires. but i also had a grey that i ran to a common ground i had.. i'm ognna have to take off the gauge and investagate.

[Matchless]

OK I found more detail. Save this diagram to your PC and open.
The grey wire is positive for the gauge lamps and goes to the positive thats there when the lights are on. Both the lamp and the gauge have a black/white to negative or ground and may be be combined into one.
There must be a yellow black wire that goes back to the tank sender unit. At the tank definitely two wires a black/white to ground and a yellow/black to the sender.
Have a look at the diagram attached

[hp1000s]

Yeah, the gray is for gauge-lighting, and if this is your 1100 you're working on, then the gauge lights are probably on whenever the ignition's on. The gauge itself only needs 12V to the gauge(wire w/orange), and a variable ground/potentiometer/tank sender between gauge ground(black/black & white wires) and the gauge.

[seuadr]

well.. the gas gauge has mysteriously started working again. since the continuity checks out on the lines outside the tank, i am starting to wonder if i've got a faulty connection inside.

[Matchless]

well.. the gas gauge has mysteriously started working again. since the continuity checks out on the lines outside the tank, i am starting to wonder if i've got a faulty connection inside.

That sounds good. If it's not the wiring, check this procedure blow to adjust the sender unit. If the wiper does not have enough tension on the sender resitance windings it can lift off and give intermittent readings, sometimes only at some different positions.

http://www.thegsresources.com/_forum/showthread.php?t=81513