gah.... i wouldn't recommend that.... and if i had to guess, i would expect a 3-position switch. the DTC for it shows a timer for invalid signal, so i don't think a momentary switch would make sense.
what i would do is follow the code far enough back to see where it is getting those mode determinations from.... if it is coming directly from a port on the processor, then you could follow the circuit(s) out to the connectors and you'll know what needs connected and how. if it coming in over SPI/SCI, then things get more fun.
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