I am trying to install a dual battery switch and I am having an issue trying to figure out if the 100 Amp solenoid is required on my 2000 Launch. At first I thought it was something the PO installed for the stereo, but following it back it the wire goes to the wake plate control on the dash. Is the 100 amp solenoid required or was this for something else, as it looks like a non-factory install?

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