Hey everyone,

When i purchased my 2005 FXST the fuel gauge always read empty, I figured okay bad gauge. Recently my girlfriend purchased me the flush HD fuel gauge and cap to replace it. I installed the new gauge and it is doing the same thing, still reading empty. How can i test to find out if the sender is bad? Any recommendations would be awesome as i really want to fix this problem.

Thanks!

 

Is it plugged in under the tank? Are the wires intact?

 

yup i made sure it was plugged in and wires intact.

 

anyone?

 

This is for a 2004 FXST but it should be the same for the 2005.

FUEL GAUGE AND SENDER TEST
NOTE
Always refer to the applicable wiring diagram (at the rear of
this manual) when troubleshooting instruments or gauges.
1. See Figure 2-18. Remove gauge. Ground Y/W wire of
fuel gauge sender located at bottom of gauge. Turn ignition
switch ON.
a. Fuel gauge must indicate FULL. If gauge indicated
FULL, gauge is functioning correctly. Proceed to
step 2.
b. If gauge did not indicate FULL, proceed to step 3.
2. Set MULTI-METER (Part No. HD-35500) to RXI scale to
measure the resistance of the sending unit. Place one
probe on Y/W and the other probe on a good ground.
a. If fuel tank is full, the reading should be 27-40 ohms.
An empty tank should have a 240-264 ohm resistance.
A half full tank will be approximately 97-118
ohms.
b. If a very high resistance or infinity is indicated on the
meter, the sender may be “open” or not grounded.
Check that sender and fuel tank are grounded by
placing one probe of Multi-Meter on sender flange
and the other probe on crankcase. Meter must indicate
one ohm or less. Replace sender if one ohm or
less was present. If a higher resistance is present,
check for poor connection on ground wire.
3. Check voltage to O/W (+) and BK (-) wire of fuel gauge
connector [117] if gauge did not indicate FULL.
a. Correct reading is equivalent to battery voltage.
b. If battery voltage is not present check for broken or
disconnected wire. Replace gauge if wiring problem
is not found.
7

 

I had the same issue with my fuel gauge - only it was always stuck on "Full". When I had the tins painted, I noticed that after fiddling with the float on the sending unit that it would hang up or bind on itself when in just the right position. I simply bent the rod holding the float ball to the side a little and have not had any issues since.

Just my $.02

Kizzle

 

Appreciate the responses, I will try those tests and also check out the float. Thanks again!

 

Did your gauge go to empty when you turned it off and go to full when turned on and never stopped anywhere in-between? That's the issue I'm having with my gauge. I have a 2004.

 

I have the same problem on my 05 FXST, except mine always reads full. Since I really don't trust a Harley fuel gauge, I just reset the trip odometer at every fill up and when I start
Getting close to 150-160 miles I start looking for gas.

 

I too have a problem with my gauge reading higher than it should, I had this problem when the bike was under warranty and the dealership had a heck of a time figuring the problem out till they realized my tank was empty and the float stuck all the way up so they made the adjustment, by bending the float rod and fixed it that way, I too rely of an average trip meter of 150 miles but I feel the bike when it gets down to a gallon or two as it'll miss occasionally as it gets low in fuel.

I do believe that for me the issue has been that I don't ride much (10,000 miles on a 2003) and the tank stays full most of the time, this maybe bends the rod up over time..

my two cents as well.