Does anyone have the schematics for a 6r3t-18c815-gd. It is the Shaker 500 with built in 6 disc CD changer and no AUX out. Upon opening it I found 3 PCB's. The mainboard, the display/control board connected to the mainboard via 2 sets of cables and the CD changer controller/DSP/CD decoder board connected to the mainboard via a solid 40 pin connector.
What I would love to do is tap into the 40 pin connector and remove the CD changer. That connector should have audio in ports. This would allow me to plug my Nexus 7 into it. That connector should also send signals from the control board. This would allow me to send control signals to the Nexus 7. It would be a simple process of how headphone remotes for Android work. When I press the Fast Forward button on the head unit it would send a signal to the headphone jack with a resistor on it which tells the Android device to Fast Forward. With Tasker I could make the Next CD button make it go to the next CD on the Nexus and so on.
If anyone has the schematics, pin-out for that connector or knows of a good way to trace down what each of the pins do via a multimeter or oscilloscope it would be much appreciated.