Does anyone have the pinout for the Prius 04-05 standard radio CD Changer plug, used by a few aftermarket products like the PAC AUX-BOX to enable auxiliary input ? Is the reason we need such aftermarket products instead of simply hooking stereo audio to the applicable pins, that the Prius radio needs to know, through other signal on the plug, that a device is actually connected, so that it can patch the audio input to the amplification system ?
The problem with that approach is that the radio has no indication of a device that would use that port audio inputs. The radio communicates with everything else digitally. So, when the radio turns on, (or rather when the car turns on), the radio and MFD poll to see what's on the AVC network. That network passes through the port so a device can identify itself, respond to and issue requests. When the device is given a green light, it presents its audio to the input terminals. Now I don't have specifics, but I suspect the audio input is shared by devices, so inactive devices have to release the line with high impedance so as to not to collude with other devices. I think that's the problem that IPod2Car had; it wasn't properly releasing the line. I suppose though you could create a CD with silent audio on it and use it when you inject your audio.
Thanks a lot for your reply DanMan32. It confirms my assumptions, that were based on other info Norm had provided me. For now I'll just hook up the Toyota AUX audio harness (with lengthened wires) to the back of the radio, at the same time I'll install Norm's CAN-VIEW2 and the hook-up for the MacMini I also wish to install (plus possibly taps into the cruise lever and accelerator position sensor harnesses). I'd like to disassemble the dash only once if I could... Best regards, Gilles
If you do decide to roll your own external audio input, here's some of the hardware information you might need. The audio input to the radio is connected to CN702 (which is a 12 pin connector). It has the AVC-LAN but still only had connection for one device from the way the radio's schematics look. When looking at the back of the radio: pin 1 is in the LOWER LEFT hand side of CN702 pin 7 is in the UPPER LEFT hand side of CN702 pin 6 is in the LOWER RIGHT hand side of CN702 pin 12 is in the UPPER RIGHT hand side of CN702 _____ _____ | 7| 8| 9|10|11|12| | 1| 2| 3| 4| 5| 6 | * ------------------- * The pins definitions are: 1: Ground 2: Right + (output) 3: Right -- (output) 4: Left + (output) 5: Left -- (output) 6: Mute control (input) 7: Ground 8: NC 9: AVC + 10: AVC -- 11: ACC/Ignition (output) 12: VCC (output)