Fuel Gauge and Sender Problem

Discussion in 'Electrical' started by Jubal, Apr 16, 2012.

  1. Jubal

    Jubal Member

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    Hi, I have read various posts on this fuel gauge and sender but could not figure out what to do. I have a fat boy FLSTF carb the gauge has everything OK only the last led doesn’t become red when I am on my last gallon it just goes off. I have tested it for volts it reads fine as for the ohms it reads from 37 on high and 280 on low. Any suggestions will be appreciated.
     
  2. R_W_B

    R_W_B Senior Member

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    Re: Fuel Gauge and Sender Test

    Hmmm I'm not sure if we should start a problem thread in the Help section but the Mods will move it if that's that case. You might want to check the Red LED diode to make sure it still works. Remove your console bolts, lift it up enough to release the tabs on the bar. Then see if you can get at the terminals of the red one for a test.
     
  3. Jubal

    Jubal Member

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    Re: Fuel Gauge and Sender Test

    I really appreciate your help on checking the diodes and will definitely like to make this test but I am not and expert and require more detail on how to do this, Thanks a lot RWB.
     
  4. R_W_B

    R_W_B Senior Member

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    Re: Fuel Gauge and Sender Test

    LEDs don't usually burn out (unless there is a high current issue on the line) but they will get dimer over time, but lots of time is required, certainly more than what the last gallon would give off on your bike.

    But if you've got voltage on it I just gave that as a stab in the dark.

    There are some touring models (I've heard) that do "not" have the red diode on the Gas. Make sure yours actually has the red one and check the connections to it.
     
  5. Jubal

    Jubal Member

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    Re: Fuel Gauge and Sender Test

    I opened the gauge and the sender completely off the bike. I connected the gauge orange wire to the positive and black to the ground or negative all the 7 blue lights lit but then a few second 6 of them go off and the 7th one starts blinking. So one thing for sure all the 7 lights work and the 7th light diode has to be working too. I then connected the sender to the gauge yellow to yellow and black to black and to battery negative. At the float on high all the 7 lights were lit bit when I lower the float to its minimum point one by one the 6 lights go off the 7th light doesn’t go off and no red light comes on. I have tested the sender for ohms and it shows 40 to 257 ohms from high to low.
    If anyone can give me advice I will appreciate it, thanks.