hyde wrote

Thanks Chris,
Oh yes, that's exactly what I did, I cut the casing(?) and then used electrical tape to secure it at ideal length. I am seeing several empty fuse slots, instead of cutting this and doing tap (I don't want to mess with existing fuses), can I just use one of the empty slots, preferably one that has optional equipment that I don't have, and switched power.

Kas63 wrote

Guys,

Been doing a bit of research before fitting my Blackvue. Been trying to find fuse locations to use for switched and constant power. Read most of the threads I can find here and yes, there are options for 'piggy backing' on existing fuses.

But I got curious... like most cars, there are slots in each of my fuse boxes with no fuses. In my innocence I assumed that these empty slots would still be powered, even if that function wasn't used on my particular configuration. My thinking being if I can find a 'spare/empty' fuse location I can use a fuse tap to access power without impacting on any existing circuit load. I've probed around with a multi-meter and every empty fuse location I try is dead, I was expecting to find at least one permanent live in one of them.

Am I missing something? I cant believe BMW install a bespoke wiring loom for each customer build on the production line. I would have thought the looms are all the same, every option catered for, and only enabled with control units and appropriate fuses.

I'm confused.

hyde wrote

Kas63 wrote

Guys,

Been doing a bit of research before fitting my Blackvue. Been trying to find fuse locations to use for switched and constant power. Read most of the threads I can find here and yes, there are options for 'piggy backing' on existing fuses.

But I got curious... like most cars, there are slots in each of my fuse boxes with no fuses. In my innocence I assumed that these empty slots would still be powered, even if that function wasn't used on my particular configuration. My thinking being if I can find a 'spare/empty' fuse location I can use a fuse tap to access power without impacting on any existing circuit load. I've probed around with a multi-meter and every empty fuse location I try is dead, I was expecting to find at least one permanent live in one of them.

Am I missing something? I cant believe BMW install a bespoke wiring loom for each customer build on the production line. I would have thought the looms are all the same, every option catered for, and only enabled with control units and appropriate fuses.

I'm confused.

That is very confusing, every other car, including my old BMWs F15 and E70 had very convenient empty fuse slots that were actually powered, I just simply slipped the hard wiring kit with fuse at the end (pictured) and it just worked. Did you test those empty slots while X5 engine is ON?

Also are you referring to the fuse block in the front or the back?

chrisnack wrote

Stop complicating this guys, fuse f27 and f72 in the front fuse panel in the passenger kick panel have everything you need. In most cars these are empty. My radar and Blackvue are wired off these two. There is no reason to run wire all the way to the back when it’s right there. There is also a ground lug there as well.

You only have to remove 3 trim pieces and only one screw and it’s all right there.

Pull up on the door sill trim with the logo in it. Then there is one screw for the piece in the corner. The screw will now be exposed after removing the door sill. Remove that and then that corner piece will pull out. The piece under the glove box has two twist retentions, and that whole piece comes down.

Fuse box is up and to the right, it faces down towards the floor. Ground lug is just under carpet at bottom.

hyde wrote

Thanks for this, were you able to confirm which one is switched and which one is constant, do you happen to have the picture of fuse tap installed? I am trying to figure out which side is load and which side is draw? When you installed the fuse tap, is the wire tail facing the door or driver side?

chrisnack wrote

Orientation doesn’t matter as far as I know, it’s 2 circuits. I believe the first slot closest/bottom is for the fuse itself and the 2nd/top slot is for the “tap”.

I will try to grab a picture of mine tomorrow. In my post way back I said which one was which for the fuses.

chrisnack wrote

hyde wrote

Thanks for this, were you able to confirm which one is switched and which one is constant, do you happen to have the picture of fuse tap installed? I am trying to figure out which side is load and which side is draw? When you installed the fuse tap, is the wire tail facing the door or driver side?

Orientation doesn’t matter as far as I know, it’s 2 circuits. I believe the first slot closest/bottom is for the fuse itself and the 2nd/top slot is for the “tap”.

I will try to grab a picture of mine tomorrow. In my post way back I said which one was which for the fuses.

eagle_bmw wrote

I didn't say either circuit would be unprotected.

Let me try again. If the fuse-a-tap is oriented correctly both fuses will have a load relative to the equipment they are connected to.

Reversing the orientation will make the bottom fuse gets both loads. It probably won't matter if the total loads are small enough for the bottom fuse but orientation clearly has difference.

hyde wrote

eagle_bmw wrote

I didn't say either circuit would be unprotected.

Let me try again. If the fuse-a-tap is oriented correctly both fuses will have a load relative to the equipment they are connected to.

Reversing the orientation will make the bottom fuse gets both loads. It probably won't matter if the total loads are small enough for the bottom fuse but orientation clearly has difference.

Hi Eagle,
Could you tell me how to check the polarity using multimeter? I am not using add-a-fuse so it would be extremely important that I plug my fuse in correct orientation so the line is protected.

Thanks in advance.

hyde wrote

eagle_bmw wrote

I didn't say either circuit would be unprotected.

Let me try again. If the fuse-a-tap is oriented correctly both fuses will have a load relative to the equipment they are connected to.

Reversing the orientation will make the bottom fuse gets both loads. It probably won't matter if the total loads are small enough for the bottom fuse but orientation clearly has difference.

Hi Eagle,
Could you tell me how to check the polarity using multimeter? I am not using add-a-fuse so it would be extremely important that I plug my fuse in correct orientation so the line is protected.

Thanks in advance.

eagle_bmw wrote

The fuse itself doesn't have polarity. It is just a metal wire so you can insert either way. Identifying the line side and the load side is pretty easy. I'd use a voltmeter set to measure DC voltage, remove the fuse and tap either side with the positive terminal with the black terminal connected to the car ground. If you can measure 12+V then that's the hot or line side. The load side without the fuse should be almost 0V. You would want to connect your dashcam to the load side.

jonatious wrote

I am trying to find a fuse which is switched during ignition, but when I try after all electronics turns off including ambient lighting and almost all fuses are still constant at 12V. I am not sure if everything has turned off completely yet. How to turn off the system completely to find a fuse which is off?

chrisnack wrote

Correct, power stays on for accessories for a few minutes after, that's a BMW thing.

F27 and F72 as stated many times in this thread are your friend.