JLG G6-42A Service Manual - Manual (Page 179)

9-23 G6-42A, G9-43A, G10-43A
Electrical System
b. Fuel Level Circuit Tests
If the fuel level sender (8) is suspected of giving a false
reading, perform the following checks:
1. If the fuel level indicator needle does not move,
check the fuel tank for fuel.
2. Check for loose or defective wiring, faulty ground
connections, and corrosion on the fuel tank sender
and wiring lead.
3. If fuel level indicator needle does not move after
ignition key switch is turned to the RUN position, use
a test lamp to determine whether current is flowing
from ignition switch to fuel level sender.
4. If fuel level indicator does not move and a faulty or
defective fuel level sender in the fuel tank has been
ruled out, and in addition, wiring and connectors
have been checked and ruled out, the fuel level
indicator is defective and must be replaced.
5. Check that ignition terminal has current and that fuse
in fuse panel is not blown.
6. Check for broken, shorted, frayed, disconnected or
damaged wiring between the fuel level indicator
wiring at the cab, fuse and relay panel, ignition key
switch, and from the fuel level sender on fuel tank
through wiring in cab.
7. Check fuel level sender. A defective fuel level sender
in fuel tank may also prevent fuel level indicator from
moving. Refer to Section 9.5, “Electrical System
Schematics,” for further information.