View Full Version : Question Any idea which fuse is always live?

07-03-2017, 08:13 PM
Hi all,

Question 2 - Any idea what fuse on the drivers side fuse panel is always live even when the car is off?
I need to wire up the dash cam however I can't figure out which fuse to use.

In the A6 C7, I used the Lumbar Support (Drivers) for the power as this was always on and worked fine for the year the cam was in but in the A7, the lumbar support fuse does not even exist although Lumbar works fine.
I'm thinking they've wired up lumbar with the electric seats controls now?

I have the following options

Anti-theft alarm (maybe this one??)
Electro-mechanical parking brake

Thanks in advance!

07-03-2017, 08:45 PM
Do you have a multimeter to check? If not i can check tomorrow when i get a chance. I only know of ones on the boot area

07-03-2017, 09:06 PM
I thought I did... I will try and look for it myself tomorrow but I have a feeling it's been thrown or stored in a "safe place"

08-03-2017, 01:18 PM
Found the MM but it seems the batteries have leaked inside so probably a dud now.

I'm thinking looking at the fuse diag/table, the Bank A Fuse 10 might be one to go for? It's a 5a fuse and is for Engine Sound, night vision, garage door opener. I suppose what I don't know is if I do not have either of these (and no fuse), does it still stay live or is there a need for vcds changes to make it think those components exist and so it should activate that fuse slot.

Otherwise I'm thinking anti-theft alarm...thats got to be 24/7 powered surely

08-03-2017, 01:28 PM
ill have a look at lunch and send u a pic of the permanent live that i find on the drivers side panel

Out of interest what dashcam are you going for, i was looking to get one too but trying to find one that fits nicely out of site without blocking any of the factory equipment on the windscreen

08-03-2017, 02:08 PM
Cheers BB

I've tried MANY dash-cams and wasted a lot of on them over the last few years but the one I have gone for and been happy with is the Thinkware brand.
I had the F750 in the A6 C7 which ran very nicely. Never once did it crash out or miss any incident. The F770 came out last year and I found depending on what version of firmware you have on the 750, you could essentially make your 750 a 770 - For me this was great as I could activate timelapse recorded when parked which essentially meant a lot more recording for less memory and battery power. I assume if there was an incident when parked, it would flip to normal record mode to capture all the details.

For the A7, I decided to get a F770 and hand the F750 to the other half for her A3

In regards to your blocking equipment - I put mine on the passenger side (left) up top and directed the lens lower. Upside is there is no blocking and looks factory/an extension of the mirror camera/sensor. Downside is it is more biased to passenger side because of the placement of the lens.
Some put it in-line with the neck of the mirror mount but I found that to be too low and too obvious that there was a camera

In any case, it's not easy to hide the camera and have a perfect central view because of our bulky mirrors, the 750 fit quite nicely on the drivers side of the mirror in the A3 because it has none of the auto-dimming/full beam sensor/speed camera and what not behind the mirror so plenty of space

Hope this helps!
Happy to put any samples on youtube for you to view.

Few other bits that may/may not be useful is the Thinkware range has speed cam database (manual update), collision detect (if you're too close in front), lane detect (if you veer off) etc but I ended up turning it off.
Finally, mine was a 2- channel , one rear and one front with the rear only needing one cable to the front camera - the front powering both front and rear camera.

08-03-2017, 02:56 PM
Thanks for the info, i checked just now and all the fuse pretty much in the center cream coloured fuse block are 12v permanent(well with car unlocked, no electrics etc active)


08-03-2017, 04:11 PM
Thanks for checking - What year is your A7?
The manual splits the bays into 3 - black, brown and red. You're on brown but the bay does not match my bay or manual
ie: yours from what I can see is 5, gap, 10, 30 from the top
Mine is 5, 5, gap, gap
In that order, it would be Infotainment, Infotainment, Front passengers seat, gap (manual states fuse 4 is missing)

I wonder if yours is pre-facelift and therefore live and now in facelift they kill them

Reason I mention this is near enough where you are should be either Drivers' seat or Lumbar support (drivers seat) but in my case, both are missing and both did not power the camera when I inserted a 5a fuse.
I will double check tonight and update accordingly

Other strange thing is fuse 8 in that same bay which is the 5a fuse two up from your multi-probe is blank on mine ... but obviously I have interior lights (no lighting pack)

08-03-2017, 04:24 PM
yes mine is a pre-FL 2012. If you look in the blank fuse locations you will see there is only a metal connector on one side, so none of them would work, im sure you know that already. i didnt check the manual what those fuses relate to but everyone i checked was 12v permanent, just tryany of the 5a ones and see which works for you :)

08-03-2017, 09:19 PM
All done! Thanks for your help. Not been out since to confirm so if I don't report any issues, it's worked.

The first issue is down to Thinkware. The red and yellow wires are wrong way so that didn't help - ie: the battery wire was actually accessory and accessory was battery. I read about this but thought they fixed it - I probably had an old batch cable.

I used :
Bank A (Black) 5th fuse from the bottom - a 5a fuse for "Gateway". In the manual, it's Bank A, Fuse 9
Bank B (Brown) 4th fuse from the bottom - a 5a fuse for "Heater for video camera, light sensor, rain sensor". In the manual it's Bank B, Fuse 9.

In my case, the red wire labelled ACC is the one going to Bank A and yellow wire labelled Battery goes to Bank B but as I said above, I think red is in actual fact the battery and yellow is acc which makes sense that the rain sensor, light sensor etc would only turn on when the button is pressed to acc or engine on mode.

Hopefully that may help someone!

Next challenge is tomorrow to try and see how to fit the rear cam. In the A6 it was perfect, a non-moving rear window and headliner. The A7, the window moves as the boot lifts and headline is not something I can tuck the wire into.
Front camera is now installed.
Ran cable up from the fusebox into the rubber seal up the door/pillar, and across the headliner (tucking the wire in) to the camera.
Only real issue is the cable does make a little bump in the seal which means the door needs a bit of a slam to shut it but this should stabilise.

thanks again!