Looks right, mine is a purple wire. The power for the temp gauge is regulated thru the fuel gauge, I think it gets 5 volts. You could check for voltage at the strap that comes from the fuel gauge. If you have an analog meter, you may see the power going on/off quickly. That's normal. If there's no voltage to the temp gauge, the bad news is that you have to replace the fuel gauge, or do what I did and just forget the factory gauge and get a mechanical one.

Bob
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