Damm...I tried to get the signal converter to work yesterday.
I couldn't...

I followed these instructions and the fuel gauge always shows full.
I checked the connections several times and the red light comes on when the instruction mode is on and finally the green light comes on.
But I couldn't get it to work, it always just showed full.









I connected the signal wire back and the gauge works as before but it looks very wrong.
I tested by moving the float so that I just got the reserve light to come on and here is a picture of where the light came on, you can see from the picture that the float is nowhere near the empy point.





I measured the ohms from the sensor of this fuel sender unit I bought from Rockauto and they are 0 = empty and 94 = full.
I measured the ohms from where the light came on, they were about 16 ohms.

Why does the gauge understand that 16 ohms means the tank is empty?

Since I had to twist the fuel sender unit to get the cover bolts in place, that could be one reason why the gauge is showing so wrong...but these Chinese parts are never of any quality.

If the tank capacity is about 20 gallons and I tested last summer by filling the tank up when the reserve light came on, it held about 11 gallons.
If I can't get the converter to work, do I have two options?

1. Install a resistor in the signal wire so I can calibrate the gauge to show correctly?
2. Bend the float arm up or down

Thanks,

 

When I first used that same signal converter I had the same issue. The gauge showed full all the time. But it worked fine on the workbench. As an experiment I ran a jumper wire from the battery negative directly to the top of the sending unit. Then I made sure the wire from the sender was connected to the ground. Then it worked fine.

So my permanent fix was to run a new ground wire from the big aluminum plate in the rear behind the tank up to the top of the sender. This fixed the issue.

 

Okay, thanks for the tip. I'll try this tomorrow.

 

Yes, the reason was the missing ground from the sending unit because I had it out of the tank for tuning.
When I added the grounding jump wire, the converter started working.

I made the necessary adjustments and installed the sending unit back into the tank, the box worked after that because it gets grounding through the mounting bolts.

This is how much fuel is in the tank and the gauge now shows 2 bar and the reserve light is on.
I will empty the tank so that 1 bar is on and fill it up, let's see how much fuel it can hold.

Thanks