Thanks for the prompt replies. I'm an electrical idiot and can't get too complicated; but in my simple thinking if Pin 85 is +12V from the ignition switch (and it is), seems the other side of the relay coil circuit (E8 from the ECM) must be Ground (negative) in order to activate the coil circuit and turn on the fan? Then anytime the fan is not requested, E8 is something other than Ground. Am I understanding this correctly and is that the "switched ground" being referenced?
Sorry to beat this to death, but am trying to understand so I can measure when the ECM has activitated Pin E8 to request the fan on and don't want to fry the ECM. So how does one detect ground and/or otherwise at Pin E8?
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