2011 G3 Prius - Gas Sensor Recalibration

I am not so sure about any of that.

I know the combination meter has inclination sensors, which it uses to correct fuel level readings according to whether the car is level, and there is a calibration procedure for those sensors.

As far as the actual level sensor in the tank, I do not believe there is anything about it that can be calibrated, by the dealer, by Techstream, or by you. If it hasn't got the right resistance-to-level relationship, I'm not aware of any solution other than replacing it,

So, you could try the recalibration of the inclination sensors easily enough, but if that doesn't turn out to fix your issue, I don't think there is any other "calibration" you can do.

 

This is how to calibrate a GEN II I don't know if it the same for your GEN III. It's pretty simple and it won't hurt to try. I had to a similar problem after replacing the instrument cluster circuit board.

 

Just to reiterate, the steps given there were captioned "recalibrating the fuel gauge", but all they recalibrate is the inclination sensors built into the combination meter to detect when the car is on a slope. The combination meter uses that information to tweak the fuel gauge reading when on sloped ground, so it might make that much of a difference if the calibration has gone off somehow.

But other than that, there is no calibration of the fuel level sensor itself, either in gen 2 or in gen 3.

 

I never knew exactly how it worked but here's my story.
Thank you for clarifying my post.
After changing the circuit board on the back of the instrument cluster when I would run the gas gauge down to the last square, I was only able to get about 6 gallons of gas into the tank. I repeated this three times with the same results. Each time on level ground.
After completing the procedure outlined in the attachment, I was able to get a little over 10 gallons of gas in the tank when the gauge was down to the last square. It's been that way ever since.

 

It seems that you may have been getting some information from less reliable sources. If you could add to your posts where you found this information, we might be able to respond in more detail.

The PDF that tkc100 attached in #3 gives the gist of the inclination-sensor calibrating procedure for gen 2. I would have recommended a person go straight to the repair manual instead (in the old 2006 edition that's often consulted, this is on pages ME-30 and ME-31). These telephone-game versions (it looks like tkc100's PDF file itself was made by watching a youtube video that Hometown Hybrids put up after looking in the manual) usually just get further and further from what you'd have learned by just looking in the manual to begin with, but the one in #3 at least still looks close enough to work.

The gen 2 inclination-sensor calibration was very much like the gen 1. Neither procedure required Techstream. By comparison, looking in the gen 3 repair manual, it appears they did away with the inclination sensors entirely, leaving nothing at all to calibrate. The fuel gauge troubleshooting instructions involve confirming the resistance of the tank level sensor (12 to 18 Ω at full, 405 to 415 Ω at empty, smoothly changing in between); if the sensor doesn't check out you replace it, if the wiring doesn't check out you fix it, otherwise you start replacing circuit boards in the combination meter.

The only fuel-gauge-related things you can do with Techstream in gen 3 are to view the current reading in the Data List, or use the Active Test to force the display to full, mid, or empty as a display test.

 

ChapmanF

Let me be clear, I only shared my experience. I do not profess to be any kind of a Prius expert. I depend heavily on individuals like yourself who give so much to this community.
You are right the procedure is in the service manual and I will add their are at least several You-tubes that are just flat wrong or very misleading. I think for that I can claim to be an expert.