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Discussion Starter #1
I replaced my fuel level sender unit in the gas tank since I thought it was bad due to the low fuel light being on all the time. Well, evidently that wasn't the problem since the light is still staying on. The wiring diagram shows one wire from the low level sender in the tank to the bulb in the dash. If it were broken the light wouldn't come on, and if it were shorted, it'd blow a fuse, no? The ground wire must be ok since the light is on. Any ideas?
 

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I'm no help but have the same problem and just been to busy (lazy) to troubleshoot it. Subscribed.
 

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Wiring schematic that I've got (which admittedly isn't the best) shows only one wire coming from the fuel level sender to the low fuel warning light too Joe.

If you've got a power wire making a dead short to ground than it should blow a fuse,the circuit should be protected.

Wonder if your low fuel warning light wire mighta got hot and melted it's way through to/or maybe it rubbed it's way through to another wire that's transmitting power and it's simply stealing power that way.
 

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Discussion Starter #4
update

Well, when I touch the 2 wires together that go from the dash warning light to the fuel level sender, with the key on, the low fuel light comes on. When they don't touch, the light goes off. So I think the problem is in the other direction, namely I bet I bought a faulty low fuel level sensor unit :mad:. I guess I'll have to take the one out of my track bike and see if it works any better. Someday...:rolleyes:. I'm tired of digging around in the fuel tank!
 

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2001 900SSie
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My guess is that the "sender" is a float switch.

With your old sender not in the bike, hold it right way up and resistance should be close to zero (light on if in circuit). Hold it upside down and resistance should be infinite/open circuit (light off if in circuit). I think the wire colours should be Brown/White and light blue. Light blue is from the fuse and brown/white to the lamp, then onto ground.

If you don't have a multimeter just hook it up to a battery with a bulb in series to see if the bulb goes on and off when doing the up and upside down check.

If it is a float switch it might be jammed with crap, so a shake or tap on the bench might release it. Odd the brand new one does the same though.

If this is not the case then it could be as some one else wrote, power from elsewhere getting to the light. Can you remove the wires at/near the sender and see if the light still still stays on? If so, then it is getting power from another wire. E.g. chafed positive powered wire shorting to the sender wire to the light.

The wiring diag is odd. The wire from the sender starts as Brown/white then changes White/brown after the first connector, which is OK, then without another connector the White/brown wire changes to Brown only at the connector pin 11 near the cluster !! ??

Unfortunately you may have to remove the new sender and repeat.

Richard
 

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Discussion Starter #6
Thanks, Punch. I've resigned myself to having to remove it. The wires work properly when not attached to the sender, so it may be stuck or a bad unit. I do need to remove it and check with a multimeter.
 

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While you are inside the tank again, you might want to think about relocating your fuel filter to outside the tank to save you having to go back inside to change it in the future. This shows it going to the regulator for EFI models, but same principle for carby models.



 

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Discussion Starter #8
Thanks for the suggestion Punch. I only replace a fuel filter very rarely, so I don't mind if it's in the tank. The problem is that to test or replace the fuel level sender, you still have to go into the tank to remove the fuel pump wires. Oh well, I've said before that I like working on my Ducks :rolleyes:.
 

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False reading

Recently my 97's fuel reserve light has been giving a false reading. When it was working perfectly the light would only come on around 140 kms from fill up.

Now it comes on just after leaving the gas station, more or less stays on until around 120kms, then goes out, and bingo, comes on again as it should around 140 kms.

Oh, and prior to all this happening, the fault first materialised as an occasional very faint on/off effect when at a steady speed on the expressway.

Anyone had a similar experience?
 
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