If test voltages with a volt meter when either the fuse on this circuit is blown or ground is not connected to the battery, then I read the 12V battery voltage on both the input of the 7805 voltage regulator and the output. I don't really understand why this is so but it must have something to do with the meter ground being connected to the battery ground.
If the fuse is good and the board is connected to the battery ground then everything reads fine (e.g. 5V on the 7805 output).
Can someone explain why the 12V on the output of the 7805 is observed in this case?
If the fuse is good and the board is connected to the battery ground then everything reads fine (e.g. 5V on the 7805 output).
Can someone explain why the 12V on the output of the 7805 is observed in this case?
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