Question On Instrument Cluster Post

[Gregm]

Not trying to hijack the “instrument cluster” post. I have started another post, so that I can ask a couple questions.

The temp and fuel gauge have 3 terminals positive, frame negative and sensor negative. If the back of the gauge is not marked how can one tell which is which? Normally can these gauges handle 12 volts or normally something on the circuit board which reduces the voltage? If I understand your (Resqueline) answer in the “instrument cluster” and the gauge can handle 12 volts. One should be able to attach a 12 volt positive lead to the positive terminal and putting a negative lead on one of the other terminals the needle should move all the way in one direction and if one moves the negative lead to the other terminal the needle should go all the way in the opposite direction true or false?

Thank you

 

[Resqueline]

True on all accounts, as far as I can remember. It's been a long time since I fiddled with those and I don't have one easily available.
I'd guess the (symetrically) middle post is the common positive. Measuring with an ohmmeter you should get the highest reading between the other two posts.