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Many devices, including most recent phones, use USB for power/charging. I added a dedicated dual USB charging outlet, which leaves the standard 12V outlet free for other things.
This is the cover plate from just above the front 12V outlet. On some models, this has an audio input jack for the stereo. Here, I've cut a hole to accept a stacked USB jack. If you look closely, there's an alignment pin at 3 o'clock, this pin fits into a corresponding slot in the dash hole (also at 3 o'clock), so the opening is aligned with that.


This is the USB jack. It's a 1775066-1 from TE Connectivity. Mouser Electronics has them for about $3.

If you cut the hole carefully and precisely, the jack will fit with the metal lips covering the cut plastic edge. The jack should be installed so the USB contacts are on the top side of each port as shown here for two reasons - that way the cable will have the USB symbol on the top side, and it helps prevent dust or loose material from getting on the contacts. So, in this picture the tab mentioned above is at the 3 o'clock position (although it's behind, so you can't see it).

USB specifications call for a nominal 5.0 Volts. But the spec allows 4.75-5.25 V. Because USB cables use fairly thin gauge wires, and charging devices often draw more than 1 Ampere of current, things work better if the provided voltage is toward the high end. That way, after the voltage drop in the cable, the device still receives >4.75 V, the point where many devices will limit their current draw. The short: your devices will charge faster.
This is the voltage regulator I used, it will take 4-35 V input, and produce an adjustable output between 1.23 and 30 Volts at up to 3 Amps. It will only lower the voltage, which is fine here, because we need to change the ~14 V automobile source to ~5.2 V for the USB. Search eBay for "LM2596 regulator," and you can find these for less than $2 (cheaper than you could buy the parts in the US), shipped from China (takes a few weeks). You hook up the input, and use a meter to adjust the output to about 5.2 V using the potentiometer on the board. When no USB devices are connected, these only draw about 5 mA (0.005 Amps) from the car, less than many stereos draw to maintain their memory when the key is off. This amount won't drain your battery, so we don't need to worry about switching it on and off, the charging ports can always be available, and you can charge your devices without needing the key turned on.

To secure the jack in the plastic plug, I used some blank printed circuit board material, and soldered it to the mounting tabs on the jack. This locks the jack into place so it can't be pulled through the front when unplugging a USB cable. You could use a bit of brass shim stock, or maybe even a bit cut from a tin can to do similar. After this picture was taken, I trimmed these a bit (along the green lines), to ensure they didn't interfere with the flexing of the tabs which hold the plug in the dash opening.

The USB Charging specification shorts the center two (data) pins together with up to 200 Ohms to indicate a charging port. Simply shorting them together works fine, here they were just bent towards each other and soldered, then pushed down out of the way. Note that each port is independent, only connect the two center pins on each individual jack.
The outside pins are power (pin 1, on the right here) and ground (pin 4, on the left). As shown here, the USB contacts are on the top. Wire power and ground to both jacks.

After wiring the jacks, I used some hot melt glue to provide strain relief for the wire and insulation. Don't force it down into the jacks - there are holes going through to the connector side and if glue goes through you may have a hard time plugging things in.

This is everything assembled, almost ready to install...

...but first, tape up the voltage regulator, so it can't short against anything.
Installed in the dash hole, and wired to the conveniently located, always on, power source immediately below. Done.


Write-up is here.
 

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Discussion Starter #3 (Edited)
This follows the USB charging specification. Most Android phones do, too. I've had both HTC and Samsung phones which follow the spec. It's typically shown by the phone as a difference between "USB charging" and "AC charging."

"USB charging" means the phone thinks it's plugged into a regular USB 2.0 port (like your computer), and it will only draw 500 mA max. That's often not enough to charge a phone in the car if you're also running GPS (Maps) or streaming media. It certainly isn't enough to charge a phone as fast as it is able. If the phone thinks it's plugged into a USB charging port ("AC charging," like the AC chargers which come with most phones), it can draw much more (typically up to 1500 mA), which is enough to both run applications and charge the battery. The ports I described look like an AC charger.

If you get one of those USB chargers which plugs into the 12V outlet, you should make sure it follows the USB charging spec. Not all do, especially the CCC (Cheap Chinese Crap) ones. The Motorola ones I've used do (with the attached cable), but may not provide 1500 mA.

USB 3.0 simply ups the "USB charging" to a max of 900 mA, more than USB 2.0, but still less than an actual USB charging port.

iThings do their own, completely non-standard thing.
 

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Yeah, given that you can just plug in a two port, USB 3.0 compatible charging adapter, this is a solution aimed at committed techies.
 

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Discussion Starter #6
Yeah, given that you can just plug in a two port, USB 3.0 compatible charging adapter, this is a solution aimed at committed techies.
It's not clear what you mean by "USB 3.0 compatible charging adapter," the USB 1/2/3 specs are separate from the USB Battery Charging specs. A USB 3.0 port can't provide as much power as a Dedicated Charging Port (DCP), as I explained above, and of course only provides an advantage for USB 3 devices, it doesn't provide any more power to an existing USB 2 device.

The ports I documented are USB Battery Charging spec v 1.2 compliant DCPs, which is what most current USB compliant devices use to fast charge. They will work with any USB compliant device. The plug in adapters I've checked draw much more current while idle. Not an issue if you drive every day, but if you leave it parked for a week at the airport and forget to unplug the adapter... well. I like keeping the power outlet available for other uses, like plugging in the charger for my laptop or an AC inverter. This also gives utility to an otherwise unused space.

But perhaps you're referring to the more recent USB Power Delivery spec? I'm not aware of any phones which can take advantage of that spec, which is much more involved - it requires intelligence at both ends of the connection and in the cable(s). It's significantly more work and expense to implement than the Battery Charging spec. I also haven't seen any power adapters which support it.

But, if you don't have a use for it, then it's just not for you. That's OK. Maybe I can interest you in a fine zombie sticker?
 

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Discussion Starter #8
That's non-standard, uses Apple's proprietary ID system, and exceeds the specification for USB ports, which are only rated for 1.5 Amps. It's got nothing to do with USB 3.0, and a device which does follow USB specs likely won't draw more than 500 mA from it.

Notice the mention of "dedicated charging cables." Those are non-standard cables which short the D pins (as I did on the jacks, above) to make the connected device think it's plugged into a proper DCP and allows it to draw up to 1.5 A (their explanation is incorrect). The proper way to support both USB specs and Apple's proprietary one is to use a smart ID chip, like the TI TPS2513A.
 

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That is why I added a switched 12v outlet using OEM parts. Nissan should have wired them like that from factory then an inverter charger etc couldnt run down battery. This was an interesting project for those with a real techy mind though.


The plug in adapters I've checked draw much more current while idle. Not an issue if you drive every day, but if you leave it parked for a week at the airport and forget to unplug the adapter... well. I like keeping the power outlet available for other uses, like plugging in the charger for my laptop or an AC inverter. This also gives utility to an otherwise unused space.


But, if you don't have a use for it, then it's just not for you. That's OK. Maybe I can interest you in a fine zombie sticker?
 

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That's non-standard, uses Apple's proprietary ID system, and exceeds the specification for USB ports, which are only rated for 1.5 Amps. It's got nothing to do with USB 3.0, and a device which does follow USB specs likely won't draw more than 500 mA from it.

Notice the mention of "dedicated charging cables." Those are non-standard cables which short the D pins (as I did on the jacks, above) to make the connected device think it's plugged into a proper DCP and allows it to draw up to 1.5 A (their explanation is incorrect). The proper way to support both USB specs and Apple's proprietary one is to use a smart ID chip, like the TI TPS2513A.
The 2011 Nook Color used the proprietary method you describe. All my current tablets (TF700t, 2012 Nexus7, 2013 Nexus7) charge at ~2A. Even my phone, a Galaxy S5 charges at 2A using a USB 3.0 micro b cable. Nothing I own still charges at half an amp.

All these devices charge at roughly the same rate using most any 2A+ charge source. So it may not be a documented spec, but it sure is widespread. And as you can imagine, its a good bit faster.

Anyway, you seem to know a lot about this.
 

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Discussion Starter #11
What makes you think your Nexuses (Nexi?) charge at 2 A? You can't trust anything reported by the phone itself - the software based gauges are simply not accurate. Just because the charger is rated for that much doesn't mean the unit will draw that much. Someone tested the stock charger/cable, and it didn't draw nearly that much. Note how it maxes out about 1.4 A, under the USB charging spec of 1.5 A. This tester compared different cables. Others have done similar. None charged a Nexus 7 at over 1500 mA, regardless of the charger.

From the first link, it's easy to see how the voltage drop in the cable reduces the current which will be drawn. That's why I adjust the voltage regulator to 5.2 V - it's still in spec, but more current will be drawn because the voltage stays higher at the device.
 

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Sounds like a good modification for those who truly need it. Apparently I don't because the el cheapo USB adapter I purchased at a truck stop for $3.99 seems to charge my phone just fine.
 

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What makes you think your Nexuses (Nexi?) charge at 2 A? You can't trust anything reported by the phone itself - the software based gauges are simply not accurate. Just because the charger is rated for that much doesn't mean the unit will draw that much. Someone tested the stock charger/cable, and it didn't draw nearly that much. Note how it maxes out about 1.4 A, under the USB charging spec of 1.5 A. This tester compared different cables. Others have done similar. None charged a Nexus 7 at over 1500 mA, regardless of the charger.

From the first link, it's easy to see how the voltage drop in the cable reduces the current which will be drawn. That's why I adjust the voltage regulator to 5.2 V - it's still in spec, but more current will be drawn because the voltage stays higher at the device.
Good info. But my stock charger is not 1.35A so it makes me wonder what else he might have gotten wrong. In any event it looks like you and I are, at worst, splitting the difference.
 

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Nissan usb ports in the blanks

has anyone tried these?

-J
 

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has anyone tried these?

-J
I personally have not, but don't see why they wouldn't work just fine. Amazon also sells a round-style set that goes right in the 2nd plug. All depends on your setup. I have seen both styles used. If you choose to use that, definitely would like to see pics then.
 

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Ok I ordered that usb rectangular one to replace a blank.....I'll post up after I get it installed....

Coming from oversea's so it says est. delivery Oct 15- Nov 2nd...I hope it comes Oct as I have time during the day since I'm working nights to install it..

J
 

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I personally have not, but don't see why they wouldn't work just fine. Amazon also sells a round-style set that goes right in the 2nd plug. All depends on your setup. I have seen both styles used. If you choose to use that, definitely would like to see pics then.
Ok, so I got it installed....

If you go on ebay and look at the listing for this UBS blank replacement you can see some very clear pictures.....after reviewing what i show you below, you can see that the blanks actually have top and bottom orientation with their design. I didnt realize this until this mod. you will see below.

Packaging as it arrived and the right side photo shows the harness connector it has, makes it easy for splicing wires and then you simply connect the connector up and done, take note the "top mounted" arrow as you can see the "square" shape that i dealt with below:


So, taking a moment to show:
USB on the left
and
BLANK on the right

This shows you they tried to make it work plug and play, but for me it did not. there was just a little bit too much plastic and the USB wouldn't "snap" into place at all. after carefully lining them up and comparing them, i noticed that i needed to remove material to make the USB match and snap into place. SO, as you can see below, I got a utility knife and carefully chipped away about 1mm of plastic on both TOP and bottom numbs and then it SNAPPED solid and worked great.



Finished - ok, so here it is installed. I wired it off the 12 volt source from the power socket. simple and close enough.

Also, I noticed something due to the blank "top/bottom" orientation, and that it NEEDS to be positioned a certain way, the dammn USB "symbol" is upside down.


also, it has a blue LED light shapped like a triangle that you can see in this finished pic



I did the install quick, i plan on going back in there and routing my wires under the dash and pop up to my proclip mount by drilling holes/notching the plastic, etc.

My proclip Magnetic mount set up - http://www.thenewx.org/forum/showpost.php?p=1534610&postcount=17

Thanks,
-J
 

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updating usage:

yes so far it works great....charges my phone faster it seems and has been working fine. looks oem and i like its placement.

-J
 
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