I have a Pioneer Avic D3, which is fantastic but has a problem.

I have had the car at the installer twice to try to find correct signal to trigger auto-dimming of display. The Avic needs a positive 12V trigger according to the installer. Nothing on the light switch works, irrespective of setting.

Only proposal is to work around using a switch.

Does anyone have any ideas on this?

 

Then either use a relay to convert to +12volts, or go off the park light wires which is +12volts, not difficult either way, good luck.

 

Thanks. Relay part I understand.

I never dug into differences between what the DRL switches on and what is switched on automatically from car's own light sensor.

Does that mean the dashboard lights and parking lights come on at same time? Couldn't I just tap the dashboard light or cigar lighter illumination in that case?

 

DRL is low beams, parking lights are not lit. Yes, dash and park lights are on at the same switch position. Don't see why not for the illumination provided it is the +12v switching and not the ground. Those wires are pretty tiny at each of those small bulbs(not sure on their current capacity or how much your radio needs), which is why I suggested just the parking light wire itself.

Relay:
85 - negative illumination from car
86 - radio ign/acc or constant
87 - same as 86
30 - new radio +12v illumination
May need to change those around depending on what the car wires rest at, don't want the relay to be on to cause a battery draw.
Personally I would do the parking light since it is only one wire.

 

Thank you very much. I will give it a go with the parking light.