I had the pleasure of working on this evil system today installing a Sat System and I tapped the 12 volt switched wire for power and ground on the cage for the sat. I didn't replace the deck I just disconnected it and when I plugged it back in it asked for the code. Luckly the day before the customer had a battery issue and had to get the code so I punched it in and everything seemed to work. She left and then activated the system and said she was not receiving any sound from the sat also stating that everything seemed to work. when I got in I noticed the dash display for the factory system was not on, not even the backlighting. Well needless to say I check both the fuses for the head unit and they where fine. is there a seperate fuse for the dash display. I did notice that there was a connector that hooked into the head unit with four wires. I check to see if the black on had continuity with ground but it didn't and I noticed 3 out of the 4 wires read 4.5 volts. Has anyone got any ideas on what I can check or how I can pin point something so I can go about fixing it? Forgive my grammer because I sometimes get ahead of myself... thanks for your time.
Check all fuses in car (both under hood and in car) sometimes the radio constant or in your case the display may be tied into the dome light or some other circuit. If that doesn't work pull the radio and display and make sure all connections are good and in the correct places. hope this helps
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2008 Scion xB
Pioneer AVIC-D3
RF 3Sixty.2 sound processor
Stock speakers (for now ;))
thats what my other installer said... I have the car coming in on my day off... how lovely thanks for the input