A129 how many amps should the fuse have?


Bit con
Use a 5 amp fuse like everyone else.

As for the orientation issue, forget about it, with a 20 amp supply it is not going to be a problem, whereas using a 15 amp fuse could end the life of your vehicle, and potentially you, if someday your cable gets sufficiently damaged that you suffer a short circuit.

So Dashoto's kit only including 15 amp fuses is improper and dangerous....Correct?

1. I should replace both outer fuses with 5 AMP then (ACC + Battery). Leaving the Original 20 AMP (Vehicle) and 15 AMP (Vehicle) Alone?

2. I am confused by https://www.blackboxmycar.com/blogs/news/how-to-use-an-add-a-fuse-kit

Fuse tap orientation. I really WANT to understand this so please explain.

A. When they refer to orientation are they meaning the A and B plugging into the fuse box? And NOT the direction the fuse is plugged into Fuse 1 and 2, Correct?

B. It states to plug in Fuse 2 and Leave Fuse 1 Empty. Presuming they are referring to A and B, are they stating that with a multimeter or LED light tester, that Fuse 2 should be getting Juice if the orientation is proper?

I.E. in my image.. I have the fuse tab with the label fuses facing downward. But are they stating that it might go upward as well. That I should remove Fuse 1 and test to see if Fuse 2 is getting Juice in the downward direction?
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UPWARD / DOWNWARD


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Thanks, but why do you reccomend a fuse that's on when the vehicle's power is on?
The A129 has a parking and the hard wire kit has this thing which safes the car battery from draining. :)

Always on = Battery Fuse. This allows parking mode to work. Hardwire kit has voltage cutoff so if it drains battery below X, camera shuts off.
ACC = Ignition. Camera runs off the Car once its started.....Not draining battery.
 
Please answer..Will swap out fuse once I have answer.

Is the fuse Orientation into the Fuse Tap what is meant by +/- or is it HOW the fuse tap (up / down or Right / left) +/- plugs into the fusebox?
 
I wonder if there is really something like a fuse direction, if I'm looking into my fuse box it looks pretty messy:
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I wonder if there is really something like a fuse direction, if I'm looking into my fuse box it looks pretty messy:

Same. I'm wondering if the fuse tap goes the same direction as the fuse - and that's the proper alignment. Or if we need to test both ways to see which one gets power with fuse 1 empty and fuse 2 with 5 amp.
 
I tested my fuse taps just now to verify work of my mechanic friend - I trust him but we did use a fuse that didn't like my car. So no harm in double checking the work we did.

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Fuse 1 = Fuse closest to fuse box
Fuse 2 = Upper Fuse (away from fuse box)

Removed Fuse 1 from both Fuse Taps. Left in Fuse 2 in Both Fuse Taps. In both tests, Fuse 2 was hot (with fuse 1 removed). From what I've read, that means my fuse taps are facing the proper direction and getting power from the fuse box direct.

Now I just need to swap out the 15 amp outer fuses with 5 amp fuses.


https://www.blackboxmycar.com/blogs/news/how-to-use-an-add-a-fuse-kit

There are two ways you can plug an add-a-fuse into a fuse slot since there are two fuse legs and two fuse slots, but there is a correct orientation to plug it in. To test which orientation of the add-a-fuse is correct you will need a circuit tester or multi meter. Put a fuse into the Fuse 2 slot but leave fuse 1 empty, the orientation that has power going to Fuse 2 will be the correct way to plug in the add-a-fuse. If it's plugged in this way, Fuse 2 is getting power from the fuse slot directly and it doesn't put additional load on Fuse 1 so it'll be less likely to blow Fuse 1.
 
...but there is a correct orientation to plug it in. To test which orientation of the add-a-fuse is correct you will need a circuit tester or multi meter.

Thanks for the detailed explanation. Too bad, that I read that one day too late, because I hardwired mine yesterday. :(

I placed fuse 1 (adjustable seat) and fuse 2 (dash cam wiring) in the same direction.

Now everything works perfect, so I wonder how would I recognize a wrong fuse direction? Would there no power to the dash cam? Or the would the adjustable seat inoperative?
 
Thanks for the detailed explanation. Too bad, that I read that one day too late, because I hardwired mine yesterday. :(

I placed fuse 1 (adjustable seat) and fuse 2 (dash cam wiring) in the same direction.

Now everything works perfect, so I wonder how would I recognize a wrong fuse direction? Would there no power to the dash cam? Or the would the adjustable seat inoperative?

Simple. Unplug power cable from Dash Camera.

Remove Both ADD a Fuse taps from the Fuse Box. Yank out Fuse 1, Keep in Fuse 2. Plug back in each fuse tap with ONLY fuse #2 inserted. Test the Fuse with an LED Fuse Tester or Voltage Meter. If the fuse lights up the LED tester (or shows voltage on voltage meter), the fuse taps are facing the right direction.

If the light does not light up / voltage meter shows no voltage. Switch direction of the fuse tap and try again. If this shows voltage, then you are now facing the proper direction.
 
Thanks for your reply, just a few minutes ago I coincidentally met some neighbour, who is a car electrition and he said there is absolutely no plus or minus polarity on car fuses.

The foto of my car fuse box, which I posted yesterday, is a pretty good evidence for that too. Also there would be a plus or minus marking on the fuse.

Seems like a pretty good urban legend, that there is a polarity on car fuses.
 
There's no "polarity" but there is a "feed" side and a "load" side. Tapping the "feed" side may overload car wiring; tapping the "load" side may overload the car fuse. I prefer the latter but with the small amount of current a dashcam uses it's more an academic point than a problem. I've never heard of anyone having any problem no matter which side of the fuse they tapped their dashcam into. Just go with what points the wires from the tap in the best direction and you're done.

Phil
 
There's no "polarity" but there is a "feed" side and a "load" side. Tapping the "feed" side may overload car wiring; tapping the "load" side may overload the car fuse. I prefer the latter but with the small amount of current a dashcam uses it's more an academic point than a problem. I've never heard of anyone having any problem no matter which side of the fuse they tapped their dashcam into. Just go with what points the wires from the tap in the best direction and you're done.

Phil

Thanks. I was told fuses can go any direction by a few people now, so this must be right. The fuse taps on the other hand have a "right and wrong" direction I believe. I.E. testing Fuse 2 without Fuse 1 to make sure it isn't being powered by Fuse 1....
 
Thanks. I was told fuses can go any direction by a few people now, so this must be right. The fuse taps on the other hand have a "right and wrong" direction I believe. I.E. testing Fuse 2 without Fuse 1 to make sure it isn't being powered by Fuse 1....
Almost right, but to be safe, fuse 2 should be powered by fuse 1, otherwise if you have two 10 amp fuses then you will be able to draw 20 amps from a supply designed to supply only 10 amps, and that could cause damage/fire.

As long as you are using 10 or 20 amp sources, this wont matter with a dashcam that will consume less than 0.5 amps, the extra current draw will not be enough to cause a fire... unless there is a short circuit :unsure:
 
Almost right, but to be safe, fuse 2 should be powered by fuse 1, otherwise if you have two 10 amp fuses then you will be able to draw 20 amps from a supply designed to supply only 10 amps, and that could cause damage/fire.

As long as you are using 10 or 20 amp sources, this wont matter with a dashcam that will consume less than 0.5 amps, the extra current draw will not be enough to cause a fire... unless there is a short circuit :unsure:

Blackbox website states that you want to test the fuse tap with Fuse 2 installed and fuse 1 empty. If Fuse 2 gets power, that's the proper direction for the fuse tap? ....And the fuses themselves have no polarity. I've been told that now by several people, including a mechanic.

So it doesn't matter which direction the fuse goes into the fuse tap?
 
There's no "polarity" but there is a "feed" side and a "load" side. Tapping the "feed" side may overload car wiring; tapping the "load" side may overload the car fuse. I prefer the latter but with the small amount of current a dashcam uses it's more an academic point than a problem. I've never heard of anyone having any problem no matter which side of the fuse they tapped their dashcam into. Just go with what points the wires from the tap in the best direction and you're done.

Phil

Are you referring to the fuse tap? Or the ACTUAL fuse itself?
 
Almost right, but to be safe, fuse 2 should be powered by fuse 1, otherwise if you have two 10 amp fuses then you will be able to draw 20 amps from a supply designed to supply only 10 amps, and that could cause damage/fire.

As long as you are using 10 or 20 amp sources, this wont matter with a dashcam that will consume less than 0.5 amps, the extra current draw will not be enough to cause a fire... unless there is a short circuit :unsure:

Wait, so you're telling me, I'm actually risking a car fire when a short circuit happens?
My fuse 1 is a 10 amp and fuse 2 is a 5 amp, from what I've read in this thread those thin cables are absolutely not able to tolerate 15 amps.
 
Wait, so you're telling me, I'm actually risking a car fire when a short circuit happens?
My fuse 1 is a 10 amp and fuse 2 is a 5 amp, from what I've read in this thread those thin cables are absolutely not able to tolerate 15 amps.
  • If your fuse 2 gets its power from fuse 1 (no power with fuse 1 removed) then there is no risk.
  • If your fuse 2 gets its power not through fuse 1 then you could draw 5 amps through fuse 2 at the same time as fuse 1 is supplying 10 amps to the original circuit making 15 amps in total from the fuse socket. In that case there is a question of how much the fuse socket can safely supply, it may be supplied by a 10 amp cable, or it may be supplied by a 100 amp bus, in the former case there is a risk of fire. Somewhat unlikely this will actually happen, but fuses are not there to protect against normal situations, they are there for when things go wrong. If you had tapped a 5 amp fuse then I would be worried by this situation, a 20 amp I wouldn't worry. Another way to reduce the worry would be to replace your 5 amp fuse by a 2 amp fuse, that should keep everything within the safety margins if things did go badly wrong. The 100% safe way to avoid the situation is to turn the fuse tap around.
 
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  • If your fuse 2 gets its power from fuse 1 (no power with fuse 1 removed) then there is no risk.
  • If your fuse 2 gets its power not through fuse 1 then you could draw 5 amps through fuse 2 at the same time as fuse 1 is supplying 10 amps to the original circuit making 15 amps in total from the fuse socket. In that case there is a question of how much the fuse socket can safely supply, it may be supplied by a 10 amp cable, or it may be supplied by a 100 amp bus, in the former case there is a risk of fire. Somewhat unlikely this will actually happen, but fuses are not there to protect against normal situations, they are there for when things go wrong. If you had tapped a 5 amp fuse then I would be worried by this situation, a 20 amp I wouldn't worry. Another way to reduce the worry would be to replace your 5 amp fuse by a 2 amp fuse, that should keep everything within the safety margins if things did go badly wrong. The 100% safe way to avoid the situation is to turn the fuse tap around.

Thanks for your detailed answer, I'm now at this point were I just have to accept that my english and technical understandings are too poor to understand what you're saying.

What confuses me the most is, that it makes absolutely no sense to turn the fuse tap arround when there is nothing like a polarity on those car fuses, how can there be one on the fuse tap?

Thanks for your patience, too bad, there are no dash cam shops which offer to build in a dash cam.
 
  • If your fuse 2 gets its power from fuse 1 (no power with fuse 1 removed) then there is no risk.
  • If your fuse 2 gets its power not through fuse 1 then you could draw 5 amps through fuse 2 at the same time as fuse 1 is supplying 10 amps to the original circuit making 15 amps in total from the fuse socket. In that case there is a question of how much the fuse socket can safely supply, it may be supplied by a 10 amp cable, or it may be supplied by a 100 amp bus, in the former case there is a risk of fire. Somewhat unlikely this will actually happen, but fuses are not there to protect against normal situations, they are there for when things go wrong. If you had tapped a 5 amp fuse then I would be worried by this situation, a 20 amp I wouldn't worry. Another way to reduce the worry would be to replace your 5 amp fuse by a 2 amp fuse, that should keep everything within the safety margins if things did go badly wrong. The 100% safe way to avoid the situation is to turn the fuse tap around.

Blackbox recommends the complete opposite. To not draw power from fuse 1 and overload fuse 1's circuit. No one can agree on anything with regard to hardwiring. I'll leave it how I have mine installed by Mechanic friend. Where fuse 2 draws its own power.

https://www.blackboxmycar.com/blogs/news/how-to-use-an-add-a-fuse-kit

There are two ways you can plug an add-a-fuse into a fuse slot since there are two fuse legs and two fuse slots, but there is a correct orientation to plug it in. To test which orientation of the add-a-fuse is correct you will need a circuit tester or multi meter. Put a fuse into the Fuse 2 slot but leave fuse 1 empty, the orientation that has power going to Fuse 2 will be the correct way to plug in the add-a-fuse. If it's plugged in this way, Fuse 2 is getting power from the fuse slot directly and it doesn't put additional load on Fuse 1 so it'll be less likely to blow Fuse 1.

Here's a guy testing the theory and claiming there's no right / wrong way on fuse taps...
 
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If it's plugged in this way, Fuse 2 is getting power from the fuse slot directly and it doesn't put additional load on Fuse 1 so it'll be less likely to blow Fuse 1.
It is true that it is less likely to blow Fuse 1.

However, isn't it better to blow fuse 1 than to set fire to the cabling?

Fuse 1 is there for a purpose - to protect the cabling.
If you choose to bypass it then it can not do it's job!

You could also make it less likely to blow fuse 1 by increasing the rating of fuse 1 - fit a 100 amp fuse instead of a 10 amp one, then it is very unlikely to blow, because the cable will be certain to blow first! This may seem a silly suggestion, but it has the same result as bypassing the fuse.
 
It is true that it is less likely to blow Fuse 1.

However, isn't it better to blow fuse 1 than to set fire to the cabling?

Fuse 1 is there for a purpose - to protect the cabling.
If you choose to bypass it then it can not do it's job!

You could also make it less likely to blow fuse 1 by increasing the rating of fuse 1 - fit a 100 amp fuse instead of a 10 amp one, then it is very unlikely to blow, because the cable will be certain to blow first! This may seem a silly suggestion, but it has the same result as bypassing the fuse.

A dashcam draws very little amperage. I doubt adding a 5 AMP fuse will cause a vehicle fire. Either way, seems some people recommend bypassing fuse 1. Others recommended (you) suggest using fuse 1 as the intermediary between Fuse 2 and the Fuse Box.
 
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