video where i check all my fuses: https://www.youtube.com/watch?v=74YimFvXEsQ

fuses that lighted up without key:

11 Moonroof (20a)

12 accessory power socket (with idk why it did since it doesnt give power to my 2 usb charger port i have.) (20a)

27 accessory power socket (same above except i have radar dectector in there) (20a)

38 left headlight high beam (10a)

39 right headlight high beam (10a)

40 TPMS (7.5a)

41 door lock (20a)

42 Driver power window. (20a)

fuses that did lightup with key.

19 to 22 confirm

19 acc (7.5a)

20 acc key lock (7.5a)

21 daytime running lights (7.5a)

22 hac (7.5a)

enter image description here

now which fuse should i use for yellow wire? (need power without key) , im going to use fuse#19 for red wire. Finally on grounding my bolts are way too tight and hard to reach. except maybe the one thats right next to my fuse box. can i use that as grounding point? enter image description here

  • A ground bolt being tight should not be a good reason for not using it. They are supposed to be tight - you may just need to get a tool that gives you the leverage to turn it.
    – Rory Alsop
    Commented Apr 11, 2015 at 8:36

2 Answers 2


If the TPMS lit up when testing, I'd use that for your constant power. I'm not sure how you are planning on tapping the power, but if you use the small straps which go around the fuse blade and insert with the fuse, place it on the side of the fuse which has the power going to it, not to the side which goes out to the TPMS system. Then ensure you have an inline fuse going to your dash cam. This will protect your dash cam without over loading the 7.5A fuse used for the TPMS. The reason I say use the TPMS is because since it only has a 7.5A fuse, this means it isn't drawing much juice in the first place and should be able to handle the additional load of the dash cam without issue. For your edification, to test for the hot side of the fuse, remove the fuse and then check both sides with your tester. The side that lights is the hot side (obviously).

For the ground, if that bracket which is holding has the bolt in it (which also holds the OBD-II DLC ... the white plug towards the bottom center of the pic) is metal, then it should be good to go for a ground. You can double check this buy attaching your probes wire end to it, then probing the fuses you just checked in the video (the ones which were hot). If it lights, you're golden. Get a crimped wire connector which is the right size to fit in the bolt, then place the connector between the bolt head and the washer.


Very descriptive answer, however I don't agree with the constant power source. In my experience I would use #42 (20a fuse) for the driver's window. Even with the in line fuse it's possible to surge the fuse and if it were to blow you'd only lose the power window on driver's side/(rather insignificant when it comes to safety). Besides that, I agree completely with the first answer.. really mostly just opinion. Parts stores do have splicers that clamp onto existing wires to avoid weak connections that causes wires to heat up ... good luck, hope I could help. I've just been wiring aftermarket electronics since 8th grade kinda a hobby I'm almost 30.

  • The whole reason for the constant power source is so the dash cam will function all the time if the OP wants ... this is their thing, not mine. Fuse taps like these put on the powered side work great and can be removed without leaving damage to the wiring system. And the driver's side window? Insignificant when it comes to safety? Did you actually mean the passenger side? Maybe one of the rear windows? Commented Apr 12, 2015 at 0:46

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