Also:
what is the button for on the front of the screen?
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I bench tested my gauge to day so i know it works, (thought i had better before i cut the wires off the plug
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)
scratched my head for a bit working out why one of the plugs had a live wire and an earth and went no where
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, so looked at the other plugs on the loom and found a plug that was its oposite, pushed them together and the gauge lit up, (i know it is silly but may be an idea to note that on the install instructions,)
i didnt want to start conecting plugs together in case i buggered up the board in the gauge,