fj40 guage cluster (1 Viewer)

[tcfreeman]

working on a fuel sending unit on a '74 fj40 the yellow/red wire going back to the fuel gauge works and the guage seems to work, but the oil gauge seems to take the same signal, in other words the oil guage is going up along with the fuel guage.

seems to be factory wired this way?

 

[pbgbottle]

oils sender should be yellow with black . fuel yellow with red . check the connections and they all source there power from blue with red

 

[tcfreeman]

The only way I can get the fuel guage to move is to have a hot positive wire going to the sending unit.

if it is just grounded the guage will not work, this is a new plastic tank so there is no ground on the sending unit through the chassis.

 

[Maintz]

Are both the sender and guage OEM? If so, and you're installing a plastic tank, ground the sender unit from one of its outside screws to the body (good idea on steel tanks as well). There should be no "hot" feeds to the sender unit, justto the guage as Jake said. Good luck!