3 wire SMAKN gauge help

[reb0957]

I could be a complete idiot.
I bought a 3 wire gauge thinking positive ground switch.
The wire coming out the back of the gauge are red yellow black.
I am thinking red + Black- Yellow switch.

It aint working. There add says red blue green wires,
Can someone please give some input on what wires are what?
Thanks

this is one i put in awhile ago i think i used 12v + input

[reb0957]

I was trying to use 38 behind the key. Could that be to much? Maybe I'll just buy a 2 wire

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yes to much volts
you can use yellow wire to key switch and black to pack ground then red to 12v+ off pack negative



this will have meter on with 00.0 showing when key is off
if you want meter on with voltage showing all the time , you take yellow wire to pack positive (BL+)

if you want the ability to turn meter off you can put a switch in the black ground wire

i only use 2 wire meters now

[reb0957]

And those Itty bitty sites are a PITA for my fumble fingers

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