Largo

2004 LS430 right tail light went out. Problem was traced to corrosion on the terminals of the REAR TRUNK FUSE JUNCTION BOX. I cleaned the wiring harness and replaced the Junction Box with a used one problem solved. But now my gas gauge turns on and looks like it is working (but reads incorrect gas level) for 10 seconds. Then it goes to off position with the low fuel warning light lit.

I looked for error codes but there are none.

I had another fuel tank sending unit from a problem a few years ago. Swapped it and same problem.

Any ideas other than the replaced junction box? Thanks for any help.

rkw77080

It probably has something to do with the replaced trunk fuse box, in particular, the ECU. The LS430 has 2 fuel gauges - the main unit is located under the driver-side rear seat, and the secondary unit under the passenger-side rear seat. Each level gauge has 3 signal wires going to the ECU. Please check to make sure they are properly connected.

Largo

Thanks for the reply.

I looked at the Luggage Room J/B and mine is similar but not the same. Mine is a 82670-50080 and doesn't have the connector top right with 18 pins.

I also didn't know there was a fuel level sender on each side. I replaced the passenger side.

I've pulled all the connectors and reseated them, no change. Perhaps the drivers side sending unit?

rkw77080