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As just about everyone here knows, the Spider has an issue with the low fuel light blinking during vigorous handling. This is mostly because Alfa didn't put any electronic damper into the circuit. I've been searching around for potential improvements to this and may have found something that'll work.
Apparently Moto Guzzi motorcycles have a similar problem, and an owner engineered a solution: it's an additional circuit that goes inline between the lamp and switch to add a delay so the light only comes on when the switch is closed for a while. Some details and the circuit design at the links below:
Motorcycle schematics and utilities.
http://www.worwig.comule.com/schematics/Lightdly.PDF
I contacted the guy and it looks like the circuit on the bike is the same as in the Spider: there's +12v through the lamp running back to the switch at the tank. When the fuel is low the switch closes to ground and completes the circuit. He suspects it'll work fine on the Spider (the wattage of the bulb may make a slight difference in performance).
Some questions:
-Anyone out there with more circuit design experience than me have any opinions on this?
-Can someone double check that I'm reading the crappy Alfa wiring diagram correctly and have the right understanding of how the original circuit works?
-Does the low fuel light switch in the sender go directly to ground or does it go through a resistor? The wiring diagram is little confusing on this point. Anyone have one out where they could measure the resistance?
I'm tempted to try building this but it won't be until I get some more free time.
Apparently Moto Guzzi motorcycles have a similar problem, and an owner engineered a solution: it's an additional circuit that goes inline between the lamp and switch to add a delay so the light only comes on when the switch is closed for a while. Some details and the circuit design at the links below:
Motorcycle schematics and utilities.
http://www.worwig.comule.com/schematics/Lightdly.PDF
I contacted the guy and it looks like the circuit on the bike is the same as in the Spider: there's +12v through the lamp running back to the switch at the tank. When the fuel is low the switch closes to ground and completes the circuit. He suspects it'll work fine on the Spider (the wattage of the bulb may make a slight difference in performance).
Some questions:
-Anyone out there with more circuit design experience than me have any opinions on this?
-Can someone double check that I'm reading the crappy Alfa wiring diagram correctly and have the right understanding of how the original circuit works?
-Does the low fuel light switch in the sender go directly to ground or does it go through a resistor? The wiring diagram is little confusing on this point. Anyone have one out where they could measure the resistance?
I'm tempted to try building this but it won't be until I get some more free time.