Installing navigation what is y91 option

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Im installing a navigation in my 2007 Tahoe Z71 with bose, rear audio controls, steering wheel controls, and rear factory dvd.
I have 3 out of the 4 connectors from factory. The nav i purchased came with the brown connector.

The brown connector (C-4) has 4 wires, 1. back up camera, 2. vss, do i need because my factory radio has the accelerated volume option, the 3rd and 4th wire (pins 8,16) is for the amplifier do i need to hook them up and were to? It says there are for y91 option only?

 

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Navigation Install help

I figured out the y91 option is the luxury amp in the cadillacs, yukons and denalis, I dont see the y91 code in the glove box so im assuming i dont have to hook it up. So all i have left is the vss wire and take it to the dealer to get it unlocked.