Power Magic Pro wiring - questions for non-electrical person

[Chuck13]

Hi all,

I have a 2016 Mercedes E350 Wagon and the car have 2 fuse box: 1 in engine compartment and the other in the trunk area. I accessed the one in the trunk area and confused as how I should wire the Power Magic Pro (PMP). I don't have car electrical experience, so I thought I will ask here.

Picture of the fuse box is uploaded below. My questions are, in relation to the picture below:

1). Looking at the fuse box, there are some fuses that are protected with colored cover and some that are not. There are yellow (bottom right), green (top), etc. Do these colored protective cover mean anything and am I not supposed to mess around with it? If yes, how do I open these cover?

2). Assuming I CANNOT use the fuses that are protected with the colored cover, can I connect PMP to any of the open fuse, REGARDLESS of the amperage? I.e. there is a red fuse with 50A - can I connect PMP here? PMP manual said max Output Current is 2A

3). For the GROUND cable, can I just tape it to the metal part of the car or do I have to screw it in?

4). I read somewhere that 12V is too low for voltage cut off. Since the PMP doesn't have 13V settings (next setting is 22.8V from 12V, nothing in the middle), anyone see the dashcam got cut off much earlier if you use 22.8V?

5). I bought two 10A fuse tap (https://www.amazon.com/gp/B001QRSBW0). Do I need to put ANOTHER fuse in the fuse tap, in addition to the original fuse? I.e. If I use the cigar lighter, which use 10A, do I put two 10A fuse in the fuse tap? I saw an installation video that show that you can wrap around the cable in existing fuse, hence one fuse is enough.

 

[Ralph2]

#5. A fuse tap uses the original fuse (from the slot you put the fuse tap in) back into the fuse tap. The second slot of your fuse tap is for the application you are going to use. ~ 5 amps is more than adequate.
#4. There is no voltage higher than (nominally 12v) on most cars. The PMP is designed to also use a 24volt system but those are rare on domestic cars.
#3. The ground must be a good one, off hand, the nut shown in bottom left would be an excellent ground, wrap a length (insulation removed) under the nut and re tighten
#2 Yes.. you could tap into any fuse.. providing you replace the fuse as mentioned in #5. The bigger issue is finding a fuse that has power when you want it. You need a source that is on all the time and one that comes on only with the key. I used the brake source for my always on and my radio for the keyed source. There "should" be a list of functions related to each fuse somewhere close.. on the cover??
#1 I have not seen the type of covers your picture shows. There must be a way to move it and allow access to each individual fuse.. but again you need to find the ones that have power when you want for your camera.
Good luck... it is not difficult.. the biggest problem.. for me.. was getting my head in position to view while my hands were available to do something.. while on my back looking through glasses............

 

[CDNinHH]

I read somewhere that 12V is too low for voltage cut off.

Yes, that is one disadvantage to the PMP. The Lukas models are better in this regard.

 

[Chuck13]

Thanks, Ralph2! A couple of follow up questions:

1). For the fuse tap, do I have to use additional fuse on top of the existing one?

The reason I ask is because I watched PMP installation video from www.blackboxmycar.com (video here) and the presenter just wrap the PMP cable to the existing fuse leg and plug it back to the fuse box. Which mean that PMP just use the existing fuse - no additional one needed.

I can get another 5A fuse for the tap no problem, but if its not needed, then I won't buy the additional tap. Also, if I add another 5A fuse, then the fuse slot will have 10A (original fuse) + 5A (additional fuse) = 15A. Is this OK for the fuse box and the equipment in the car designed to take only 10A?

2). On which fuse I need to use, I found the fuse diagram hidden next to the spare tire - under the cargo platform (weird location, given that it's not in the manual). I think the issue I have if finding WHICH fuse is OFF when the car is OFF. I am planning to use the following:

1). PMP YELLOW cable (for always ON power): ambient light fuse (bottom left - 30A green fuse).
2). PMP RED cable (for OFF power when car is turned off): airbag fuse (bottom left - 5A green fuse). I believe airbag does NOT operate when the car is OFF

Alternative fuse for the PMP red cable that I believe is OFF when the car is turned off:
- Fuel pump: 25A
- Windshield washer pump: 15A
- Heated rear window: 30A
- Cigar lighter: 15A

 

[Chuck13]

Yes, that is one disadvantage to the PMP. The Lukas models are better in this regard.

Yup, I looked at the Lukas but the front camera is too big for me.

 

[CDNinHH]

Sorry, I meant the Lukas battery prevention devices.

See this: https://dashcamtalk.com/battery-discharge-prevention/

 

[CDNinHH]

1). For the fuse tap, do I have to use additional fuse on top of the existing one?

You should really have 2 fuse taps. One for the Yellow wire ( always on circuit) and another for the Red ( switched power) all the fuse taps I have bought come with a fuse, you choose which size. 5 amp fuses are are plenty, actually I would use 3 amp. So when you put the tap in you remove the original fuse and place that in the bottom slots, the 3 ( or 5) amp goes in the top.

the presenter just wrap the PMP cable to the existing fuse leg and plug it back to the fuse box.

Bad idea for a number of reason.....Get a fuse tap.

PMP RED cable (for OFF power when car is turned off): airbag fuse (bottom left - 5A green fuse). I believe airbag does NOT operate when the car is OFF

Personally I would not fool with the airbag circuit, that is too important to have anything go wrong. Choose the cigar lighter.

 

[Chuck13]

You should really have 2 fuse taps. One for the Yellow wire ( always on circuit) and another for the Red ( switched power) all the fuse taps I have bought come with a fuse, you choose which size. 5 amp fuses are are plenty, actually I would use 3 amp. So when you put the tap in you remove the original fuse and place that in the bottom slots, the 3 ( or 5) amp goes in the top.

Do I have to get fuse tap with the same fuse rating as the original one? I.e. the ambient light use 30A fuse, so I have to get a 30A fuse tap PLUS 5A fuse. 30A fuse goes to bottom and 5A goes to top. Correct?

Personally I would not fool with the airbag circuit, that is too important to have anything go wrong. Choose the cigar lighter.

Sound advice. I am trying to pull out that plastic cover (from picture - green one on the top) to get the cigarette lighter fuse tap but that cover is so damn tight. Still trying... Oh, and looking at the fuse tap that I bought (picture below), the cable looks too thick to route through the opening in the plastic cover. I wonder if I really need this cover.

 

[Ralph2]

As others have mentioned stay away from ANY safety related fuses.. If.. it works.. I will attach a picture of a fuse tap with details. The YouTube video showing wrapping a wire around the leg of a fuse should be removed..it works.. but is a very bad way to do it.

 

[Chuck13]

As others have mentioned stay away from ANY safety related fuses.. If.. it works.. I will attach a picture of a fuse tap with details. The YouTube video showing wrapping a wire around the leg of a fuse should be removed..it works.. but is a very bad way to do it.

Thanks for posting the picture! I am getting closer to the truth now, but I am still puzzled on the last question (posted in thread #8):

Do I have to get fuse tap with the same fuse rating as the original one? I.e. the ambient light use 30A fuse, so I have to get a 30A fuse tap PLUS 5A fuse. 30A fuse goes to bottom and 5A goes to top.

The fuse tap I ordered is rated 10A.

 

[Ralph2]

Thanks for posting the picture! I am getting closer to the truth now, but I am still puzzled on the last question (posted in thread #8):

Do I have to get fuse tap with the same fuse rating as the original one? I.e. the ambient light use 30A fuse, so I have to get a 30A fuse tap PLUS 5A fuse. 30A fuse goes to bottom and 5A goes to top.

The fuse tap I ordered is rated 10A.

If..I understand your question. Yes.. you put the fuse you took out back in the fuse tap.. the fuse tap goes back in the slot and "that" circuit is now back the way it was. Then.. you put whatever size you need in the second slot of the fuse tap.. attache the (PMP) wire to the pigtail.. and you are good to go.

 

[Chuck13]

If..I understand your question. Yes.. you put the fuse you took out back in the fuse tap.. the fuse tap goes back in the slot and "that" circuit is now back the way it was. Then.. you put whatever size you need in the second slot of the fuse tap.. attache the (PMP) wire to the pigtail.. and you are good to go.

I was referring to the Amp rating for the fuse tap. Right now this is what I have:

- Fuse from original equipment (from the fuse box): 30A
- Fuse tap (rated max 10A)
- Fuse for the PMP (bought extra): 5A

For the fuse tap, do I need to get a fuse tap with rated max Amp of 35A = 30A (original equipment) + 5A (for PMP)?

Sorry for the basic question.. it's confusing to me.

 

[Ralph2]

If.. your fuse tap is rated for 10 amps then trying to put a 30 amp load thru it is a bad idea. Why.. do you need the source to be from such a highly rated fuse. Most folk pick something that is closer in line to what the fuse tap is rated as. There must be fuses in the 10 ~ 7.5 amp range that will provide the function you are looking for.. "always on" or "on with key only".

 

[Chuck13]

My car have two fuse boxes: one in the cargo and the other in the engine compartment. I cannot route the wire easily from the inside of the car to the engine compartment fuse box without taking apart the dashboard area. The fuse box picture I posted above is from the cargo area, which is the easiest for me to route the cable.

There are only a few option for me on which low Amp fuse to use from the cargo area fuse box because:
1). Some are covered in the plastic cover and the fuse tap is too thick. To take out the cover, I have to take apart the cargo area, which is a lot of work and I have never done it.

2). The fuses that are no covered but have low rating seems to be essential for the cars operation. Based on the picture above:
- 10A (Red): Stop/Start Engine System
- 7.5A (Brown): Keyless / Antenna Module / Theft Alarm / Engine Electronics
- 5A (Orange): Airbag

The ambient lighting is unfortunately 30A. Even the cigarette lighter is 15A.

 

[CDNinHH]

For the fuse tap, do I need to get a fuse tap with rated max Amp of 35A = 30A (original equipment) + 5A (for PMP)?

Those fuse taps are all basically the same. When you say the fuse tap you bought is rated for 35 amps do you mean that is the fuse that came with it? What you want to do is take the fuse out of the spot you want in your car, don't worry about what the amperage is as long as it is about 15 amps or more, insert the fuse tap, put the fuse you removed from your car into the bottom slots ( closest to the spades), put a 3 or 5 amp fuse in the top slots. That is all there is to it.

 

[Chuck13]

Those fuse taps are all basically the same. When you say the fuse tap you bought is rated for 35 amps do you mean that is the fuse that came with it? What you want to do is take the fuse out of the spot you want in your car, don't worry about what the amperage is as long as it is about 15 amps or more, insert the fuse tap, put the fuse you removed from your car into the bottom slots ( closest to the spades), put a 3 or 5 amp fuse in the top slots. That is all there is to it.

No, I was referring to the Amperage rating of the fuse tap itself.

But I think I answered my own question: I bought a couple of fuse tap that can take 20A on EACH fuse slot (https://www.amazon.com/gp/B0144F7E1O). It stated that the fuse tap can "use with standard ATO/ATC fuses up to 20 AMP for each slot."

 

[Ralph2]

Not wanting to confuse the issue but.. the right and wrong way to install a fuse tap was recently discussed here https://dashcamtalk.com/forum/threads/fuse-taps-using-the-hot-side-aka-wrong-side.16700/

 

[Chuck13]

Thanks Ralph2! For some reason, this thread didn't show up when I search for it.