The service manual delineates very clearly the Ohm readings on both the high and low side of the gauge.
Besides that, you can simply remove the fuel gauge from the bike, then plug it in an operate it manually to see if your gauge drops to 1 bar. If you do not want to do that because the fuel gauge sender is in the tank, you can simply get a few resistors of the value shown in the service manual and place them into the bike's circuitry and the dash gauge will read whatever it is supposed to for the float being in that position. According to the manual, the fuel sender should read between 9 to 11 Ohm for a full tank, and 213 to 219 for an empty tank. So grabbing two resistors, one in the middle of each of those ranges, should show you the correct number of bars on the dash. You can find which wires from the schematic but if you have any trouble, let me know and I will tell you what connector and what the wire colors are to jump with the resistors.
VERY IMPORTANT: there is a built- in delay (called hysteresis) in the reading of the fuel level on the dash! It is there so that the gauge does NOT respond to the fuel sloshing around in the tank, which would drive some people absolutely nuts (probably most people I guess). So you cannot just swing the float to one end of its travel to the other and watch the dash change; instead you MUST put the float in a single position and wait for the ECU to average the readings and decide this new one is legitimate before it will be displayed. In my own experience, the reading is quite slow, perhaps 20 or more seconds for a response.
You can also buy a used fuel level sender on Ebay and use that to check the dash display. I just looked and they are available from around $10.
I <believe> that you will never, ever get [no] bars but instead the fuel range is from one bar to all of the bars. Once the fuel gauge on the dash drops to one bar, the next trigger is the low fuel warning and when that trips, the lowest bar on the fuel gauge flashes continuously ON / OFF in one- second intervals.
Brian
I think you guys are correct in that the functions of the float and bulb do not relate in regards to level indication. It is possible that the final 2 LED segments do not extinguish because the bar for the float may need to be bent a little. I did replace the original float that had previously indicated just fine... you know... before the electrical event, so I'm skeptical about my indications.
My OCD just keeps kicking in. I really wish I had a decent schematic that showed the signals from the float and bulb. They disappear into the cluster and the magic happens.
Now, if I could get my hands on a used, known-good bulb, then I can replace the one in my fuel pump and eliminate the final piece of this puzzle. I would rather not spend the $250+ on a new pump tho. That would certainly feed my OCD!
Does anyone have a busted fuel pump that I can scavenge a bulb from? The same approach worked with the ABS pump when I swapped the electronics.
Shoot me a PM.