K11 Owners Group

joeangi · Posted: Wed Apr 07, 2010 11:20 pm Post subject: Fuel gauge problems

Finally got around to replacing the fuel gauge. The PO told me that the old gauge was bad, and kept blowing the fuse. I checked it out, and he was right, every time you plugged it in, fuse 1 would blow. I have been riding without one, as the low fuel light works fine.

I got a new VDO 301-107 and wired it up tonight....nothing no needle movement at all. The backlight works. Fuse 1 is not blown...Anyone have a first choice as to what I should check?

Thanks for any help.
Joe

PS I did not Calibrate the gauge (yet) I have about a half a tank of fuel.
_________________
1994 K1100RS
1986 K100RS

RAL88 · Posted: Thu Apr 08, 2010 5:59 am Post subject:

Here is how I wired mine up.

_________________
Rich

"If it ain't broke, take it apart and make it work better"
*************
'96' K1100LT-SE
'97' R850GS-R

joeangi · Posted: Thu Apr 08, 2010 7:40 am Post subject:

Dear Rich,

I wired mine the same. I had found your picture last night before I wired it up. Very helpful photo.

Still, when I turn on the bike, the gauge does not move.

Joe
_________________
1994 K1100RS
1986 K100RS

RAL88 · Posted: Thu Apr 08, 2010 7:51 am Post subject:

I am guessing you have already checked the plug from the sending unit in the tank?
_________________
Rich

"If it ain't broke, take it apart and make it work better"
*************
'96' K1100LT-SE
'97' R850GS-R

joeangi · Posted: Thu Apr 08, 2010 9:28 am Post subject:

I had checked it when I put it all together, but I will check it again tonight. The gauge does move when I ground the yellow wire. Since it is getting power, should I still lift the tank, or can I assume that it is plugged in?
_________________
1994 K1100RS
1986 K100RS

RAL88 · Posted: Thu Apr 08, 2010 9:54 am Post subject:

Can you open the gas cap and reach the float with something to move it up and down to see if the guage moves. The float works on simple resistance so if you are getting power from the float sending unit to the gauge I would think that you would see it move somewhat as you move the float from one exteme to the other.
_________________
Rich

"If it ain't broke, take it apart and make it work better"
*************
'96' K1100LT-SE
'97' R850GS-R

joeangi · Posted: Thu Apr 08, 2010 10:06 am Post subject:

Just went out and moved the float arm...nothing. Going to pop up the tank later...

Just to be sure, there is no other wiring than the 4 pin connector on the tank, right? That brings power to the fuel pump.

I just unplugged the fuel pump wiring and grounded the yellow...and the gauge did not move. When I ground yellow at the gauge, it goes all the way up. It appears that I have a problem with the yellow to the gauge...

Joe
_________________
1994 K1100RS
1986 K100RS

joeangi · Posted: Thu Apr 08, 2010 12:41 pm Post subject:

Just ran a jumper wire from the yellow wire on the plug up to the gauge, no change. Should I be looking at sending units? What is the test for a faulty sending unit?

Thanks,
Joe
_________________
1994 K1100RS
1986 K100RS

Flying Duck · Posted: Thu Apr 08, 2010 1:00 pm Post subject:

The resistance between the ground (brown) and the fuel level sender (yellow) should vary from roughly 0-90 ohms when the float arm is moved to it's extremes.
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93 LT (x2)
94 RS
86-97 K75F(K75/100/1100 Frankenbrick)
86 K75C w/paralever, hi perf cams,TURBO!
91 & 92 K75Ss
91 K1
86 custom K100
14 WR250R
IBA #17739 (SS1K, BBG, 50CC)
Buy parts HERE

joeangi · Posted: Thu Apr 08, 2010 1:17 pm Post subject:

Just tried to get the resistance....it shows open. I guess the sending unit is suspect.

Joe
_________________
1994 K1100RS
1986 K100RS