Temp gauge pegs to hot when sending unit wire is attached.
Do you mean it does that with cold engine...or are you saying it's overheating?
there is insufficient ground to make the circuit...the tester goes berserk~
There is a short to ground. Either the sender is defective or wrong for your application or there is a bare spot on the wire coming from the sender and it is touching something metal. HTH. -Jim
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