W169 power supply to the CDC: cut-off time?

[GLK]

What is the cut-off time for the power supply (and the trigger) wires to the CDC in W169?

The CDC is gone, along with the other MOST bits, and I wanted to utilise the conveniently located positive feed - for a multi-camera switch box, and a left mirror camera.

I thought the CDC would be completely powered off after 20 minutes or so, but I have waited longer and both the blue-black, and the red-white wires were still on? Perhaps I should've tested with the glovebox lid closed, but again, I always thought the car goes to low power mode (as in switches off most bits) when no opening / closing of doors, etc for a period of time - so shouldn't really matter the lid was open?

As an alternative solution, I wonder if a standard voltage-sensing DRL controller would work as a cut-off switch, for anything I connect to these wires? Can't see why not, but happy to be corrected

 

[GLK]

Turns out the CDC is (was) powered permanently, with wake-up via MOST.

Still doesn't explain why there are two +12V wires (I was sure, one was a trigger).

Anyway, decided to fuse tap an empty switched power slot, and feed it to CDC fuse slot out pin (basically relocating the 7.5A CDC fuse), so I can still utilise the existing harness.

(Just in case someone else is looking for the info, following replacement of Audio 20 with an aftermarket head unit, and removal of CD changer)

 

[richard]

GLK, the connector has 3 wires, Ground, +12 and MOST-Wakeup - I imagine the MOST-Wakeup is being pulled up to 12v somewhere.
The power to audio components on older cars is permanent and devices are woken via MOST (either by the appearance of light or the wakeup lead). On newer ones it goes off after a couple of hours or if battery gets low just to ensure a badly behaving audio component doesn't kill the battery.
R

 

[GLK]

Thanks Richard, makes sense now - I knew one of the wires (blue-black) was the wake up one, just didn't realised MOST used the actual wire.

I'll use a fuse tap to re-route switched power to the CDC fuse slot exit, and will ignore the trigger wire.