Electrical Problem

[Fddlefoot]

Have a question hope you can help with before I start tearing things apart. About a week ago I lost my low fuel light on my 79 special immediately checked the bulb it was not that and put it off for the time being,but a week later my battery (less than year old) is suddenly drained enough not to start the old girl. I did notice Sunday that it didn't seem to turn over as well but rain made me forget next 2 days till wouldn't start today. So any ideas before I start guessing. THANKS AHEAD

[TopCatGr58]

Hey there Fddlefoot,

The wiring diagram for the 79Sf for the fuel warning light is wrong!
It shows a dark green wire at the bulb, along with a black ground wire? It should be a Yellow power wire, and the dark green wire goes to the "Sending" unit at the tank. IT's not really a sending unit, just a THERMISTOR that is OPEN while it's being kept cool submerged in fuel. But once the fuel level drops, then it warms up, and makes contact completing the circuit to ground and thereby lighting the warning light!

The Thermistor may have gone bad, but you'll want to check the wires at the connector. It should read OPEN until the fuel is low. However, not sure what it'll read if it's not connected to the green power lead?? Check the green wire, it should have some voltage on it, possibly 12, but not sure! Good Luck.
T.C.

[Fddlefoot]

Thanks

Okay will check that presumed the indicator went bad but now guessing short since drained battery or could bad indicator do that?