Fuel gauge reads prematurely empty

It's certainly possible. I installed a larger capacitor to avoid having the same problem a few years down the road, and this additional capacitance could have the unintended consequence of throwing off the fuel gauge. If that's the case, I believe that I could add some resistance to the level signal and make it read much closer. Too bad that I took a wrecked Gen2 Prius to the metal recycler a few months back. I could have pulled the tank had a level sensor to experiment with.

 

Might be worth pursuing the wiring schematics to see if there’s a connection between the combo meter and the fuel gauge

 

You need to check all connections on the CM. There is one connection that is connected to another connector by a ribbon cable and you disconnect one end of that at the CM end. It sometimes comes loose at the other end, but you don't think to check it because you didn't intentionally disconnect it. Make sure you check that one in particular.

 

Or you could pop the rear seat base out and test the sender resistance when the gauge is (prematurely) reading empty. I would expect that yours is much higher than the 110 ohm spec for "empty".

Posted via the PriusChat mobile app.

 

I repaired mine with the higher ( double capacitance ) with no ill effect. I agree with checking the small connectors on the combo meter