OK.. I need some N20 help.. It's a weird one..

[Pyrotechnic]

Glad things worked out with the diodes !

Originally Posted by Super73

So I have spoken to 2 of my EE friends.. If I understood right, the coild side of a relay has a V drop but the same A pull. This equates in less total W.. So I might take your advice and put the WS, FPSS and TPS on the incoming +12v side vs the ground..

The switches have none to very little resistance. Thus, they can be treated as piece of wire in the circuit. They will see the total power, voltage, and current of the entire circuit as calculated by ohm's law.

Furthermore, all the electrons that leave a voltage source must return. All those electrons that went through the positive side of the circuit, also flow through the negative side. The switches see the same amount of electrons, whether on the positive or negative side.

Doesn't matter where the switches are.

BUT, if that window switch uses some sort of integrated circuit chip that provides a path to ground when the condition is met, it has to be on the ground side. I don't know the schematic but this sounds like the case, especially given that maximum current rating. Though you could set up the window switch to trigger a relay, which would let the switch provide either a 12V+ signal or a ground, and would give it a very large current rating.