430 2009 Scuderia PDF 9 Fuse Blowing

And don’t have a picture of the valve controller? Probably in the engine bay at the back of the car. If you have a Forza controller, You only need two wires for that switch to work. The other two are for illumination. You could remove both of those and see what happens. If you can send a clearer picture of the back of the switch and identify the valve controller we can remove those two wires and rule that out

 

Jumper wires on the backs of those switches are often seen. They probably provide common grounds for both the switch function and the backlight function.

For example, on the front lid switch...

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...there is a jumper wire on pins 2 & 5 (as you have). Note that the graphic shows the pin side of the connector, not the wire side.

This tells us that the switch is sending a ground to the controller to activate the system. The controller should be sending some kind of power to the switch on pin 4, but measuring the voltage may not be straightforward if the controller circuits are transistorised.

If the switch illuminates when you turn on the lights, you should have 12 volts for the backlight on pin 3 of the socket. I don't know why the guy who rewired the switch replaced the standard yellow/red backlight wire with a black wire.

 

Is this for information only or are you wanting to know how to hook up the switch to the valve controller? I’ve forgotten if we had a diagram for the valve controller.

I can’t read the writing on the spade connectors on the right hand side.

 

Is connector "1" a wire from the other switch (which has a yellow/red wire on it)? Yellow/red is backlight power

Here is how a Sport switch is wired up on a 360

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The "output" of the SPORT switch is a ground on pin 4 (when selected). The jumper wire between pin 2 and 5 provides a permanent ground to pin 5. You could just as easily swap the wires on 4 and 5 and have the output on pin 5 (but the ground jumper wire would have to go to pin 4).

Do you know which wire goes to the controller?
Do you have power on any wires other than the spade connector with the "1" on it? (assuming that is from the other switch's yellow/red wire). "1" should have 12 volts with exterior lights turned on.

 

You don't need to trace them through the car.

Logically, this is how it should be hooked up (your spade numbers are in pink)

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You don't need to know switch pin numbers, just follow the photo.

The small jumper wire between 3 and 4 suggests that it is a common ground, not a power wire. It doesn't matter if 3 or 4 are swapped around.

I would check for some kind of voltage on wire 2 with the key on (from your exhaust controller). Put the black probe of your voltmeter to a good chassis ground. If no volts, swap your red and black voltmeter probes (if they are red and black).

 

P.S. With the key off, you could also confirm that your 3 & 4 spades go to chassis ground (using an ohmmeter).