I was just curious if anyone has done this. The tricky part is I would like to use this switch and I want overdrive to be on when the cover is closed (switch open). Can this somehow be done with a relay (or 2)?

 

Nope. Would need a momentary toggle.

 

Would does it have to be a momentary switch? I don't see why an on/off wouldn't work.

 

Why do you need a guarded switch for overdrive??

It won't work like you want it to because the PCM is set up so that the digital input function (overdrive toggle) is triggered on the rising edge of the signal. That is, it's triggered by the circuit changing state, after which it ignores the input (signal from button) until the circuit goes open again to reset the logic.

If you wired that switch to the existing wires, then to disable overdrive you would have to close the switch (turn it "on") and to re-enable it you would have to move it to the "off" position, then back to the "on" position again.

You COULD make it work the way you want, but it would probably involve at least two one-shot relays and probably a handful of common double-throw relays too. Either that or a logic controller ($$) which you would probably have a hard time finding one that operates on 12VDC... most are 24VDC or 120-240VAC. An Arduino could probably do it, not sure on supply voltage for those though since I ain't ever messed with one.

Either way... lots of work.