Help needed - Android Head Unit not getting power?

[PNotts]

Good Morning,

I hope you are well. I need some assistance please with my head unit in my card, a Ford Mondeo 2009 TDCI.

Recently the factory installed cd6000 started switching off, aux not working , so as it was on its way out I thought I'd change it.

However I am having even bigger issues with my Android Head Unit now. When it's plugged in it drains all my battery but this doesn't always work either and switch on.

I read somewhere that cutting the permanent live is a good way of stopping the drain but I'm also worried about it not switching on all the time so think there is more to it.

Yesterday I took a multimeter to the power pins to see what is coming through. I was unable to take the pins out but was able to take measurements which are below.

Pin 9 - 3.4V (engine on) - 0V when off
Pin 10 - 0V on or off
Pin 11 - 0V on or off
Pin 12 - 0V on or off

Pin 13 - 0.68 (engine on) - 0.6 engine off
Pin 14 - No cable
Pin 15 - 0V
Pin 16 No cable

The above don't really seem right to me, would I get different readings if I took the pins out and ensured I had a proper connection with the probes?

I have never really had anything to do with changing/checking audio so any assistance would be greatly appreciated.

If anybody needs any photos or for me to check anything happy to do this and upload for help

Thank you,
Philip

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[Lasherž]

It sounds like your ignition sense (pin 16) or your can bus + is some how getting linked to battery + (pin 15) that's not normal, it should be separate. The Can bus + and - control the signal for listening to music with the car off in accesory mode (at least on VWs) while the ignition controls the on position switching. If it's staying on all the time then something is shorting the wires that ordinarily are linked to the key position with the always on bat+.

It's strange that pin 15 has no voltage. You might have a blown fuse in that case, but make sure you're making contact with the pin.

 

[PNotts]

Thank you for your help
You were right about the blown fuse,didn't even cross my mind to check that. Replaced it and pin 15 has shot up to 12.66v

Oddly only pin 13 & 15 are used,I was in the assumption pin 16 should be in use as well which is ignition power only.

The radio doesn't work without the key in the ignition so not sure what the permanent live does,could I swap this to pin 16 which is ignition only so not pulling power through permanently?

 

[Lasherž]

Thank you for your help
You were right about the blown fuse,didn't even cross my mind to check that. Replaced it and pin 15 has shot up to 12.66v

Oddly only pin 13 & 15 are used,I was in the assumption pin 16 should be in use as well which is ignition power only.

The radio doesn't work without the key in the ignition so not sure what the permanent live does,could I swap this to pin 16 which is ignition only so not pulling power through permanently?

The permanent live only uses enough power to keep the memory of the date and time for the radio as well as the settings alive in the memory chip. That's if it's set up correctly (which is to say, the radio should be off without the key). The power we're talking about running from B+ is absolutely miniscule when done correctly and the car is off. If it loses b+ when the car is off then you'll end up annoyed on the other side from never having a functional clock and all of your EQ settings resetting constantly.