12V ACC hookup location?
 

So I added a radar detector and dashcam to my 2019 Q7. Ran the wires down the side pillar and its into that compartment on the driver side of the dashboard. So now I'm looking for a switched 12V power location to connect it to. There is a row of fuses in the side compartment, but all seem to have constant 12V power. Under the dash is sealed up like a drum. Anyone know where I might tap into some switched power that turns on with the ignition? There is a 12V "lighter" plug in the center console but I'm not sure of an easy way into that.

Thanks.

Aren’t there fuses under the dead pedal?

Yes there are, but the problem is finding one switched with the ignition. All the fuses in the side dashboard cavity are always powered, even the fuses for items that don't have power when ignition is switched off. I suspect that the car computer can switch anything on or off and that this switch is AFTER the fuse, so fuses don't seem to be switched. I would rather not, but I may have to buy a cheap eBay low-voltage cuttoff, and set it to turn on at 13.3V and off at 12.8V. So when the car is running (and charging) the voltage goes up and everything turns on, shut off the car, voltage drops to 12.6V and everything shuts off. Not ideal, because it always draws a few ma. but better than nothing.

There are multiple threads on people who’ve done taps for radar detectors and cameras. One guy tapped at the mirror. Another guy tapped under the dead pedal.

Mirror wouldn't work because radar detector has a remote, and the remote has to be mounted lower, with power coming in there. I will check under the left foot rest. Certainly lots of fuses there. The question is, are any switched? So far, I haven't found one.

You’re way over my pay grade here. Hope you find a solution.

When testing fuses, you may want to make sure you wait a while after shutting down the car and not open any doors in case the fuse power times out after a while. That may be how others found a switched source in the foot panel fuses. I was never able to find one myself.

Instead, I ended up tapping off the back of the 12V outlet in the rear cargo area and running the wire up under the carpet on the sideboard. I documented that with photos somewhere on the forum, but I can't seem to find it right now. Here's a different set of pics with the same idea:

https://www.audiworld.com/forums/q7-.../#post25064230

There is switched power under the driver foot rest fuse panel. I tapped 12V ACC for TPMS display from there.

Thanks. I'm going to see if I can tackle it today.

Turned out pretty easy. Under the left foot rest, there are 5 rows of fuses, and the center panel, labeled "D" on the users guide. Fuses 6,7, and 10 are not used, and they seem to be switched ACC fuses. Took a 2A fuse, soldered a wire to the left side. I used a screwdriver to enlarge the plastic on the left side a bit, then plugged in the fuse. Works great.

I heard, but haven't tried it yet, but heard when the start-stop system restarts, the radar detector might restart from the voltage sag, but Valentine One sells a "blackout protector" (basically a capacitor) to prevent this.