2016 Jeep Renegade, USA, Beats Premium Audio w/Nav
I've been trying to figure out how the factory amplifier is receiving signals from the head unit. My findings are very curious and somewhat perplexing:
1) The Data CAN BUS relays all EQ and volume adjustment information from the HU to the Amp. The task of actually raising an lowering volume and adjusting EQ actually happens inside the amp.
2) The four wires from the HU to the AMP that are identified by numerous internet sources as the Front Driver Side (DS) Front and Passenger Side (PS) are actually dummy wires. They measure at [email protected] MHz. In fact, I de-pinned all four wires from the harness with absolutely no change in sound quality. All front and rear speakers functioned as normal.
3) The four wires from the HU to the AMP that are identified by numerous internet sources as the Rear DS and Rear PS actually carry a full-range signal for the left and right side channels, respectively. Here is the kicker: REGARDLESS of volume on the head unit, these wires ALWAYS measure at [email protected] MHz. The are always sending constant voltage to the amp.
4) Conclusion - If keeping the stock HU, any additional aftermarket amplifier additions must tap into the signals post-amp (@ the white plug from the amp to the speakers). The reason for this that all of the EQ and volume control is happening inside the amplifier from the signal being sent from the HU through the Data CAN BUS wire. If you were to hook up an aftermarket sub/amp from the "rear" wires of the HU, your amp/sub would be at the same volume at ALL times because the rear wires are sending a constant 3.5V...no matter how far up or down that you turn the volume knob on the HU.
Gray Plug from HU into Amp - Wiring Pin Positions:
3) Violet - I believe that this is a dummy wire
4) Yellow/Blue - I believe that this is a dummy wire
5) Green/Black (-), Front AND Rear, PS, full-range master signal
6) Orange/Blue (-), Front AND Rear, DS, full-range master signal
8) White (-), Data CAN BUS
14) Violet/Black - I believe that this is a dummy wire
15) Yellow/Black - I believe that this is a dummy wire
16) Green/Red (+), Front AND Rear, PS, full-range master signal
17) Orange/White (+), Front AND Rear, DS, full-range master signal
19) Blue (+), Data CAN BUS
I am not a certified technician. These are my observations. They may not be correct. In fact, I hope that someone can prove me wrong or have data proving that my observations are incorrect. Use at your own risk.
I have some more installing to do on my system. But in a couple of months, I will consolidate all of my different posts into one large FYI document.