[argtv4rlo]

The fuel, oil, & water temp gauges all seam to be reading low on my 73 GTV?
I am wondering if there is a voltage stabilizer or something else.
What are A & B on the wiring diagram?

 

[slowcreek]

First thing I would do is refresh that clump of ground wires under the left side of the dash. TONS of things ground there. remove the bolt and nut. Clean all the eyelets both sides, and reinstall securely.

Gauges work on variable ground. Bad ground can cause bad readings.

 

[alfaparticle]

The gauge has 3 terminals - GND, 12V and signal in. With IGN on check between GND and 12V and verify full voltage between them then check each one individually to battery or engine GND.

 

[argtv4rlo]

I took the ground under dash apart and clean it put it back together and put a temporary wire to neg battery.
No change?