Bad fuel gauge?

The tank units do not ‘send’ anything, Jerry - they just passively pass various amounts of electrons from ground - and ‘ground’ is an abstraction until you connect to it…

I appreciate your points, but, like Doug I’m loth to change my semantic views…:slight_smile:

xj6 85 Sov Europe (UK/NZ)

Well, if you can was a term ‘varying ground’ (where “ground” doesn’t vary, then I … and millions of others … can use the well know term "sending unit:.

“Ground” is a specified and recognized reference point and path for the return current … oh wait, maybe there was a “no return” policy in place?

No matter what you say, “ground” (in metal bodied vehicles) is a reference point and the return path for the circuit.

“Ground” can be negative or positive (remember those). You can also ‘vary the connection to ground’ (using things like corroded terminals or variable resistors).

But “ground” itself doesn’t change and is not variable.

Try this: at a sending unit (that won’t send anything, so don’t be afraid of it), use a meter and measure between your “varying ground” point and actual ground while moving the non-sending unit float up and down, watch the meter for indicator change (analog or digital)

Does the meter vary (indicating change)?

Yep … but your “ground” did not. That is the reference point you measured to.

Your varying measurement was showing that the “path through the sending unit” was varying.

Don’t believe it? Disconnect the ‘ground path’ of the sending unit from “ground” (the meter’s ‘ground’ goes nowhere) and retest.

Dang! The sending unit still varies without being connected to ground.

People are loth to do various things. Lothness seems to be a common human trait. :sunglasses: