Hey Everyone,

I just signed up after reading this thread and finding it very helpful.
I plan to sort out my AUX input but have some additional plans that I would like some help on for while I have the MMCS out.

So firstly I found this very useful. It's an explanation of what all the ports do on the back of the MMCS.
https://pinoutguide.com/Car-Stereo-M...-_pinout.shtml

I have converted my Delica D5 into a camper van and have an auxiliary battery that I run a number of things off. My plan whilst I am sorting Aux connection for music, is to wire the MMCS up to the Auxilary battery allowing me to switch the system on whilst the car is completely off , thus allowing me to play music without running the starter battery down and ultimately stranding myself in the middle of nowhere. Below I have listed my thoughts on the process. I am not an electronics expert so would be very grateful to hear some thoughts.

From the above Link my observations are:
- Pin 5 on the "5 Pin Navi Power Supply Connector" labelled "Battery +" is the Power input for the MMCS.
- Pin 10 on the "17 Pin Audio Power Supply Connector" is also labelled "Battery +" and is the power input for the speakers.
- Pin 2 of the "5 Pin Navi Power Supply Connector "is labelled "PS-R". I believe this is a Power Supply regulator.
- Pin 6 on the "7 Pin External Equipment Connector" is labelled "AMP ON".

My first thought for confirmation is: Can I run a DC power cable to a switch that switches the power source from the car battery to the Auxillary Battery, running power to both the Pin 5 and Pin 10 on their respective connectors in order to "switch Power on" when the car is off?

My Second thought is: Will the PS-R function with a separate power source? If not how do i incorporate that?

And finally a smaller thought, I am assuming that the "AMP On" pin is running power to the AMP from the MMSC? Would that be fair to assume or do I need to find the amp and run power to that too? I feel like it logically makes sense that the power is coming from that Pin? But please correct me.

Really looking forward to hearing back from you.

Thanks guys

Tristan 17 Pn Audio Power Supply Connector - Pin 10 is the "Battery +”