Fuel Gauge Question
Tourer
Joined: Jan 2010
Posts: 304
Likes: 1
From: Woodburn, OR. USA
Perhaps the sending unit inside the gast tank is manfunctioning, or the guage itself is wacked... here's a copy and paste of the trouble shooting proceedures from my '06 service manual. It's all I have, but you should be able to use the logic pattern to trace something out... hope it helps!
● Sender or fuel gauge not grounded.
THEORY OF OPERATION
With ignition switch ON, the fuel gauge is connected to +12 volts. Current flows through the gauge and variable resistor in the fuel gauge sending unit to ground. The sending unit float controls the amount of resistance in the variable resistor. Inoperative gauges may be caused by three circumstances.
With ignition switch ON, the fuel gauge is connected to +12 volts. Current flows through the gauge and variable resistor in the fuel gauge sending unit to ground. The sending unit float controls the amount of resistance in the variable resistor. Inoperative gauges may be caused by three circumstances.
● Sender or fuel gauge not grounded.
● Malfunction in sender or fuel gauge.
● Broken or disconnected wire from ignition switch to fuel gauge.
Use the FUEL GAUGE AND SENDER TEST to test suspect components.
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.
Remove gauge. Ground Y/W wire of fuel gauge sender located at bottom of gauge. Turn ignition switch ON.
a.
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.
b.
If gauge did not indicate FULL, proceed to step 3.
2.
Set MULTI-METER (Part No. HD-35500) to RXI scale (that's Ohms scale, can look like an "Omega" sign on some meters) to measure the resistance of the sending unit. Place one probe on Y/W and the other probe on a good ground.
Set MULTI-METER (Part No. HD-35500) to RXI scale (that's Ohms scale, can look like an "Omega" sign on some meters) 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 ohms resistance. A half full tank will be approximately 97-118 ohms.
If fuel tank is full, the reading should be 27-40 ohms. An empty tank should have a 240-264 ohms 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.
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.
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
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.
Advanced
Joined: Mar 2008
Posts: 92
Likes: 0
I am having the same problem, it has power there and when I removed the power wire from the sending unit the gauge dropped to empty so I know the gauge works. I only have a chiltons manual and it doesn't say anything about the sending unit at all so I hope someone here can help me out with the removal and troubleshooting of the sending unit itself. I took the screws out of it and that sumbitch wouldn't budge so before I pull out some tools I want to make sure that Io am not missinng something.
Tourer
Joined: Jan 2010
Posts: 304
Likes: 1
From: Woodburn, OR. USA
Your scoot is 14-yrs. old (according to your signature), so I did an eBay search for a service manual for your model and year and came up with this for $17.00 (shipped).
Click-on the link:
http://cgi.ebay.com/ebaymotors/FXDL-...Q5fAccessories
It seems like a very cheap investment to get you where you need to go. I bought the CD version manual for my scoot off eBay for about the same cost as this one and it is an invaluable resource to me as I'm a DIY'er/tinkerer. You can also print it out if you need a "hard copy" to work from as well, and it sure beats chewing up a $100 bill to get a "factory one" through the dealer.
Hope that helps!
Click-on the link:
http://cgi.ebay.com/ebaymotors/FXDL-...Q5fAccessories
It seems like a very cheap investment to get you where you need to go. I bought the CD version manual for my scoot off eBay for about the same cost as this one and it is an invaluable resource to me as I'm a DIY'er/tinkerer. You can also print it out if you need a "hard copy" to work from as well, and it sure beats chewing up a $100 bill to get a "factory one" through the dealer.
Hope that helps!
Advanced
Joined: Mar 2008
Posts: 92
Likes: 0
thanks for the reply, I agree that a factory service manual would be helpful in many situations I am not sure it would specifically answer the question that I have. Most service manuals simply say "remove" and leave out necessary info such as if a 4 foot prybar would be a suitable tool to break that damn thing loose which it seems I may need because that thing does not want to budge with any other hand tool I have thrown at it that I would consider "sensible". I was just wondering if others have had to remove the sending unit from an older model and could share some insight.
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Outstanding HDF Member
Joined: Jul 2010
Posts: 2,427
Likes: 2
From: Smack Dab in the Middle of Louisiana
thanks for the reply, I agree that a factory service manual would be helpful in many situations I am not sure it would specifically answer the question that I have. Most service manuals simply say "remove" and leave out necessary info such as if a 4 foot prybar would be a suitable tool to break that damn thing loose which it seems I may need because that thing does not want to budge with any other hand tool I have thrown at it that I would consider "sensible". I was just wondering if others have had to remove the sending unit from an older model and could share some insight.
What more needs to be said!!!/???
Last edited by SteveO-ll; Sep 13, 2010 at 05:52 AM.
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