Got it. I will try this over the next few days.
Is there a way to check my spare temp gauge on my bench?
Sure, use the battery under the hood or take battery to the bench. Hook negative battery test lead to gauge sender terminal and tap positive battery test lead on gauge 12V terminal to see it go to hot...or hook up pos and tap neg. If you remember, I corrected myself and said the gauge case is not grounded. I am not sure, but safer not to ground case.
Use an inline fuse on positive battery test lead.. Use whatever size fuse is used on truck for the gauge.
I use my battery charger for testing, but it is the old school style 10A. Not variable amp/trickle/automatic.
