Jeep Wrangler Forum banner
  • Hey everyone! Enter your ride HERE to be a part of JUNE's Ride of the Month Challenge!

1 - 11 of 11 Posts

·
Registered
Joined
·
93 Posts
Discussion Starter · #1 ·
Hi WF, I've been a member here since June of 2012, but only have a post count of 5, so yeah, I'm a lurker. I spend most of my forum time on JKOwners, but nonetheless appreciate the information available here. I've found some of the audio threads to be particularly helpful and thought some of you might have a whiz-bang solution for a difficulty I've run up against.

I recently added a Kenwood Excelon KDC-X998, single DIN head unit to my 2012 Unlimited. It came with the base factory radio and I wanted to add NAV without breaking the bank. I already had a sturdy RAM mounting system I used for my iPhone and occasionally, my iPad Air, so I decided to go with a cheaper single DIN HU and pick up a used iPad Mini for a dedicated on/offroad NAV unit, as well as iTunes, Pandora, etc.

Everything has worked out great with one exception. I began to notice that the iPad Mini (connected via the rear USB input) was not getting charged well. At first I thought it was just because of my short hops around town, but then I began to suspect the KDC-X998's charging capability. I checked, and sure enough, the HU only charges at 1 Amp (and the iPad Mini needs around 2 Amps).

So here's the question. Is there some means of electronic wizardry whereby I can keep the iPad connected to the USB port for better function and sound quality, but feed in an additional charging source that will supply what it needs in order to not operate at a charging deficit? Seems to me that it should be possible, I'm just not electronically educated enough to know how to go about it.

Thanks in advance for your help and suggestions.
 

·
Registered
Joined
·
2,468 Posts
I understand and appreciate what you're trying to do. Unfortunately, there is no way to do it. Here's a possible work around. When you need to charge the iPad, connect it to a compatible 12v charger and stream audio via blutooth. Switch back to the radio's rear usb when done charging.
 

·
Registered
Joined
·
6,299 Posts

·
Registered
Joined
·
125 Posts
It's kind of a long shot, but you might be able to use a powered USB hub. You'll need to find one with a power brick that outputs 12v so you can cut off the brick and wire it into the Jeep.

Very similar to Tweak's idea and i can't guarantee the HU will recognize it, but it's possible.
 

·
Registered
Joined
·
2,468 Posts
It's kind of a long shot, but you might be able to use a powered USB hub. You'll need to find one with a power brick that outputs 12v so you can cut off the brick and wire it into the Jeep.

Very similar to Tweak's idea and i can't guarantee the HU will recognize it, but it's possible.
He won't find one because, by design USB itself only puts out 5 volts max. The amperage of a USB charger or power brick, by design, ranges from 1A - 2.1A at 5 volts. Anything above 5 volts and you'll melt the USB cable and damage the attached equipment.
 

·
Registered
Joined
·
125 Posts
He won't find one because, by design USB itself only puts out 5 volts max. The amperage of a USB charger or power brick, by design, ranges from 1A - 2.1A at 5 volts. Anything above 5 volts and you'll melt the USB cable and damage the attached equipment.
Sorry, but You're wrong.

The only concern i have is the HU not being able to recognize it with their limited software. As i said, it's a potential long-shot. But not because they don't exist.

OP: Note that without the 4amp limiter in the power brick (you'd have to cut it off or use an AC inverter) i'd highly suggest that you NOT charge more than 1 device at a time with it. Make it draw more than 4 amps and you could fry the hub. I'd also make sure to put an inline 3 amp fuse just in case.

The Sabrent HB-U930 is a premium 7 Port High Speed USB 3.0 Hub that is designed to maximize compatibility with USB 3.0 devices, including power-hungry USB-powered hard drives, scanners, etc, with its provided 12V/4A power supply. Supplies up to the 1.5A per port and 2.4 amps from the two charging ports

Hub Controller

The Sabrent HB-U930 features per-port overcurrent protection to safeguard your connected peripheral devices against damage or data loss due to overvoltages.

Not Just a USB Hub, Also a Fast USB Charger
The Sabrent HB-U930 features two USB fast charging ports that provide high power (2.4 amps per port) under Fast-Charge Mode2. Taking up only one AC outlet, it gives you the ability to simultaneously fast charge two power hungry devices

Compatible Charging Devices (Smart Charging Port Only)
All Apple devices: iPhone 6+/6/5S/5C/5/4/4S, iPad mini 1/2, iPad Air/4/3/2
All Android devices: Samsung Galaxy S5, S4, S3, HTC, EVO, One X; Samsung Galaxy Note
Tablets: Samsung Galaxy Tablets

System requirements:
* Mac OS 9.1 & higher
* Windows XP /Vista /7/8/8.1
* Linux 2.4 or above

Package contents
* USB 3.0 hub
* 12V/4A power adapter
* USB cable
* User Manual
 

·
Registered
Joined
·
2,468 Posts
That's a USB 3.0 hub. I did not reference USB 3.0, so I'm not wrong.

The iPad Air is not designed to the USB 3.0 specification.

I highly advise not attempting to wire that hub into a vehicle. It will probably even overpower the inverter in some of the JK models.
 

·
Registered
Joined
·
125 Posts
That's a USB 3.0 hub. I did not reference USB 3.0, so I'm not wrong.

The iPad Air is not designed to the USB 3.0 specification.

I highly advise not attempting to wire that hub into a vehicle. It will probably even overpower the inverter in some of the JK models.
The hub is however, Backwards compatible. The devices don't need to be USB 3.0

I've worked in IT for over 15 years, and have been modding computers for longer. I install all my own car audio, and have even done 2 complete CarPc builds in the past few years.

I assure you my knowledge on the subject is quite reliable.

FYI, Running chargers off a basic ac inverter is... unreliable. It has to do with the way the inverter generates the AC waveform. For it to work well, the Inverter needs to generate what's called a "pure" sine wave. They are available, but expensive. You wouldn't want to do it with a plug in, or the stock rubicon one.
 

·
Registered
Joined
·
93 Posts
Discussion Starter · #9 ·
Thanks for all the input folks.
@Tribble, the USB hub idea is interesting. Hadn't thought of that, but it looks like a good possibility. I know you said they're backward compatible, and that is what I would have assumed, but just to clarify . . .

The HU specs say it supports USB 1.0/2.0. So if I understand correctly, in essence the 3.0 hub with a 2.0 device at each end, is just going to be kind of like having a 4" manifold with a bunch of 1" pipes coming in and going out, correct -- overkill, and not living up to it's potential, but still serviceable in the application?

If that doesn't work, I may try to locate a USB pinout and see about modding something up. My concern there is injecting noise into the data stream because of broken shielding, but if it comes to that, I'll try it.

Thanks again to all.

Scott
 

·
Registered
Joined
·
2,468 Posts
The hub is however, Backwards compatible. The devices don't need to be USB 3.0

I've worked in IT for over 15 years, and have been modding computers for longer. I install all my own car audio, and have even done 2 complete CarPc builds in the past few years.

I assure you my knowledge on the subject is quite reliable.

FYI, Running chargers off a basic ac inverter is... unreliable. It has to do with the way the inverter generates the AC waveform. For it to work well, the Inverter needs to generate what's called a "pure" sine wave. They are available, but expensive. You wouldn't want to do it with a plug in, or the stock rubicon one.
Small world, as I've been working in IT for over 25 years. So, I can assure you that my knowledge on the subject is as reliable. In addition, my father is a mechanic and owns a repair shop. I've been turning wrenches since I've been able to hold them. I've also done my share of car audio and alarm installs.

A regular USB 1.0 or 2.0 socket has four pins, and a USB cable has four wires. The inside pins carry data (D+ and D-), and the outside pins provide a 5-volt power supply. USB 3.0 ports add an additional row of five pins, so USB 3.0-compatible cables have nine wires. In terms of actual current (milliamps or mA), there are three kinds of USB ports dictated by the current specs: a standard downstream port, a charging downstream port, and a dedicated charging port. The first two can be found on your computer, and the third kind applies to wall and car chargers.

In the USB 1.0 and 2.0 specs, a standard downstream port is capable of delivering up to 500mA (0.5A); with USB 3.0, it moves up to 900mA (0.9A). The charging downstream and dedicated charging ports provide up to 1500mA (1.5A). USB 3.1 supports a power draw of 1.5A and 3A over the 5V bus.

There are plenty of USB chargers that break these specs and most are of the wall-wart variety. Apple’s iPad charger, for example, provides 2.1A at 5V; Amazon’s Kindle Fire charger outputs 1.8A; and car chargers can output anything from 1A to 2.1A.
 

·
Registered
Joined
·
125 Posts
Thanks for all the input folks.

@Tribble, the USB hub idea is interesting. Hadn't thought of that, but it looks like a good possibility. I know you said they're backward compatible, and that is what I would have assumed, but just to clarify . . .

The HU specs say it supports USB 1.0/2.0. So if I understand correctly, in essence the 3.0 hub with a 2.0 device at each end, is just going to be kind of like having a 4" manifold with a bunch of 1" pipes coming in and going out, correct -- overkill, and not living up to it's potential, but still serviceable in the application?

If that doesn't work, I may try to locate a USB pinout and see about modding something up. My concern there is injecting noise into the data stream because of broken shielding, but if it comes to that, I'll try it.

Thanks again to all.

Scott
It "Could" work is the best i can give you. HU's are notorious for their limited compatibility.

I've added a similar usb hub in a car. But when i did, it was attached to a CarPc, not a head unit. In the end, you'll at least have a port in the car that you can charge the pad from, But i can't guarantee that any data transfer will take place between the HU and the device. Might have to go Bluetooth in the end.

Powering it shouldn't be an issue. But you will want to be sure to use a switch, or a switched power input, such as from the dash 12v socket. This will ensure you can limit battery drain when the vehicle is not on.

I'd err on the side of a manual switch hooked to the battery, i'm not too keen on CAN-bus systems but i know that the power flicker (as experienced with some led light) would likely cause issues if you tap the wrong thing.
 
1 - 11 of 11 Posts
Top