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Hi, I have found that when using Android Auto in the car and on my smartphone while being plugged into the USB port, my phone battery is still draining battery life. This is quite a problem when you are using Waze in Android Auto for a long ride, so I have elected to just use my smartphone plugged into the cigarette lighter instead and to use the Waze app just from my phone instead of the car's screen. This is a disappointment as I would have liked to have used Waze on the larger screen on my car.

Has anyone else had this problem?
 

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Hi, I have found that when using Android Auto in the car and on my smartphone while being plugged into the USB port, my phone battery is still draining battery life. This is quite a problem when you are using Waze in Android Auto for a long ride, so I have elected to just use my smartphone plugged into the cigarette lighter instead and to use the Waze app just from my phone instead of the car's screen. This is a disappointment as I would have liked to have used Waze on the larger screen on my car.

Has anyone else had this problem?

I discovered that yesterday when I "Needed" to use it for the first time to charge y phone. I may be wrong, but I seem to recall something about using the 2nd row plugs for charging? I have not tried that.
 

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I regularly commute 400 miles - 6+ hours. I connect Android Auto and use it the entire time and my phone is charged 100% at the end of my drive. I agree, something else like the cable is a problem.
 

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Pretty sure they are 2.5amp plugs which is whats needed to charge and power mapping apps at the same time. However a bad plug/wire can cause this. But its also a common issue the alternative is a high quality cigarette USB adapter.
 

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I'd try a different cable, aftermarket cables are for the most part junk. Perhaps, you have one that supports AA, but can't handle the load to fast charge. Here is a good article on it.
https://blog.banggood.com/your-cable-could-be-slowing-down-your-charging-speed-31493.html

Very good point and probably the problem. I couldn't charge it from my battery power pack either - using the same charging cables. Will test it later today using the one that came with the phone.
 

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I had this issue when trying to use Android Auto on my Galaxy S7 with my 2018 Legacy - the S7 just burned so much battery running the CPU for Android Auto that it couldn't keep up with the 500ma(or 1A? can't recall) the Legacy was giving it. Bought a Pixel 2 last year which was either more efficient or just not broken like the Samsung was and even with the relatively slow charge rate, I end up gaining battery percentage. If you're using an older phone.. it could just be the phone.
 

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I had this issue when trying to use Android Auto on my Galaxy S7 with my 2018 Legacy - the S7 just burned so much battery running the CPU for Android Auto that it couldn't keep up with the 500ma(or 1A? can't recall) the Legacy was giving it. Bought a Pixel 2 last year which was either more efficient or just not broken like the Samsung was and even with the relatively slow charge rate, I end up gaining battery percentage. If you're using an older phone.. it could just be the phone.
Yeah, the Legacy was set for 1A. Trickle charge for a phone is 500ma (when they're charging overnight). That's where we've stepped things up now - the new generation all have 2.1A charging ports. We also have the phone cord discussion with our customers frequently - a lot of time cheaper cables are ONLY charging cables, they don't even have the second set of wires in them for data.
 

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Yeah, the Legacy was set for 1A. Trickle charge for a phone is 500ma (when they're charging overnight). That's where we've stepped things up now - the new generation all have 2.1A charging ports. We also have the phone cord discussion with our customers frequently - a lot of time cheaper cables are ONLY charging cables, they don't even have the second set of wires in them for data.
this was one of my few forehead smacking "why the **** did they do that" items on my Legacy, so glad to hear they got it sorted for the Ascent!
 

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This issue comes up often so I always make an attempt in vehicle forums to explain it. USB charging is actually a lot more complicated than most people realize. The latest USB ports are designed to supply a specific electrical current based upon a standard specification depending upon how a device is connected and interacts. In order to understand this better, you have to look at it from a design engineer's viewpoint. I'll try to explain this as non-technically as possible because not everyone interested in this here is an electrical engineer. There is a lot more to this but it's beyond the interest of most people here who just want to know what's going on.

Standard USB cables usually have four wires: Power: VCC (+5VDC) and Ground, and Data: D+ and D-. Using a combination of these wires there are three basic modes of operation:

When the data lines are in normal use (i.e. transferring information), up to 500ma (.5 amp) maximum power is normally supplied by the USB specification. This is the Standard Downstream Port (SDP) connection configuration and is the most common connection when using a smartphone as a connected device.

However, if the data lines are properly manipulated, a handshake protocol occurs and the connected device can call for more current (up to 1.5A for USB 3.0). This is the Charging Downstream Port (CDP) connection configuration. This is the most sophisticated connection. Your phone may or may not employ this feature based upon its software and hardware configuration.

If the two data lines are shorted by the connected device or the cable, with no data communication at all, then the current will be set to deliver up to 1.5A, depending on what the available power source can handle. This is primarily used for chargers. This is called the Dedicated Charging Port (DCP) connection configuration.

This is primarily why you may see different charging times and capabilities when connected to the Ascent infotainment system. If you wish to know more, keep reading, if not you can stop here.

In a USB connection there is usually a "host", most often a computer, but in this case the Ascent's infotainment system (which is a computer), and the connecting device. The connecting device can be a smartphone, a USB thumb drive, a USB hard drive, etc.

It's not the primary function of the host to charge a connecting device. The primary function is to exchange data. However, it's also recognized that the host is responsible for powering a connecting device that does not have its own source of power, such as a thumb drive. Therefore the USB spec calls for 2.5ma-500ma (900ma w/USB 3.0) of current to be nominally available to power a connecting device. This is the Standard Downstream Port (SDP) connection configuration. If a device needs more than 500ma, then it's expected to supply its own power. This is why some USB disk drives have their own external power source and some don't, depending on whether it can operate with only 500ma. A smartphone supplies its own power, but its battery runtime is limited, so it may wish to be charged using this available host current. You can charge a smartphone's battery with only 500ma, but it'll probably be significantly slower than desired.

Thanks in part to Apple (who didn't like supplying chargers for their connecting devices such as the iPod), it was later commonly recognized that the host should also supply power for charging. However, the host may be a laptop on battery power or with limited internal power capability, or in the case of the Ascent, it may be running only on the car's battery at times. So the host is not going to simply give up more of its potentially limited power to a connecting device by default without being asked. Also, simply supplying more current by default may potentially cause issues with or even damage some sensitive connecting devices. Therefore, the connecting device needs to somehow ask the host for more power. Since the USB connectors prior to USB 3.0 only had two power wires and two data wires (plus an extra ground), the easiest way to do this was simply to effectively short out the data wires. Then the host knew the connecting device was in "charge mode" rather than "data mode" and would (at its own discretion) supply up to 1.5A for charging purposes. This is the Dedicated Charging Port (DCP) connection configuration. In this mode, data cannot usually be exchanged. Also, please note that some so-called "charging cables" attempt to force this mode by shorting out the data connectors internally. This may or may not work depending on how the host is designed to react. This also often causes a lot of confusion about USB cables. People think "charging cables" have thicker wires and thus can draw more current. The ampacity of USB cables has only a minor effect on current draw in short lengths. Usually most decently made USB cables can draw enough current to supply 1.5 amps in lengths under a few feet. Only the cheapest cannot. So it's rarely just a cable issue when you feel USB charging is too slow.

Finally, it was later recognized that a USB connecting device may want power for both data use and charging at the same time, such as in the case of smartphones, or that a connecting device simply needed more power than the default 500ma. So a more sophisticated way was designed for the data lines to request more current from the host. In this way, data could still be exchanged while the device was being charged and the required amount of current could be supplied (up to 1.5A). However, this mode requires that both the host and the connecting device are designed and programmed to establish and understand the handshake protocol and that the host is willing and able to supply more power. This is the Charging Downstream Port (CDP) connection configuration.

So the Ascent may have all three modes, but unless the connecting device (your smartphone) is designed to use CDP mode, it won't perform the necessary handshake and it'll be stuck in the lower current SDP mode. You can use a charging cable to attempt to force it into the higher current DCP mode, but then you'll lose the simultaneous ability to data transfer while charging.

So again, it's more complex than you'd think, but I hope this clears up USB charging for everyone.
 

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Folks, I charged a Samsung Galaxy Note 8 and now charge a Samsung Galaxy Note 9 while using Android Auto for both navigation and audio, every single driving day. They're massive phones with massive batteries (4,000mAH for the Note 9) that are very power hungry when charging (and even more so when running Navigation at the same time).

If the front ports are not charging your phone, try a better cable. I made a list elsewhere of the ones I've used.
 

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Folks, I charged a Samsung Galaxy Note 8 and now charge a Samsung Galaxy Note 9 while using Android Auto for both navigation and audio, every single driving day. They're massive phones with massive batteries (4,000mAH for the Note 9) that are very power hungry when charging (and even more so when running Navigation at the same time).

If the front ports are not charging your phone, try a better cable. I made a list elsewhere of the ones I've used.

I forgot to do a follow-up post from my comment this morning. This afternoon when I used the cable that came with the phone vs aftermarket stuff, the phone charged right up. The day before, when I had the problems & critical need, I was losing juice while it was plugged in.
 

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I discovered that yesterday when I "Needed" to use it for the first time to charge y phone. I may be wrong, but I seem to recall something about using the 2nd row plugs for charging? I have not tried that.
Use the 2nd row plugs if you want to plug in a phone, but don't want it to connect to the head unit for Android Auto or Apple Carplay. Either set of outlets will charge the phone just fine.
 

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Use the 2nd row plugs if you want to plug in a phone, but don't want it to connect to the head unit for Android Auto or Apple Carplay. Either set of outlets will charge the phone just fine.
YEP! Great tip!!!

My best friend uses an iPhone, and I own a Note 9... so, his charging is relegated to the 2nd row to prevent his phone from taking over the stereo. :tango_face_wink:

I've got a dedicated cable hanging out of the 2nd row USB just for him.
 

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Perhaps my post above was a bit too technical, I'll be more succinct.

If your phone is not charging fast enough or well enough, it's probably not the cable or a malfunction, it's probably because you're stuck in Standard Downstream Port (SDP) mode and therefore you're only getting a 500ma charge instead of 1.5 amps. This is quite common with many vehicle's USB data ports and some smartphones.

This would be because:
You're using the front ports while exchanging data and your smartphone does not support the high current Charging Downstream Port (CDP) mode.
-or-
You're using the front ports while exchanging data and your smartphone does not support the Ascent's interpretation of the CDP mode.
-or-
You're using the front ports and the Ascent does not support CDP mode (unlikely because others are not experiencing this issue).

If you can successfully charge your smartphone using the rear USB ports, which only use Dedicated Charging Port (DCP) mode, then you'll know one of the above is likely true.

Keep in mind that even if your intention is only to charge the phone, when you use the front ports you are connecting to a computer (the infotainment system) and the data lines will begin to exchange data. Unless both your smartphone and the infotainment system's CDP mode are fully compatible, or you use a charging only cable, you'll get stuck in the low current SDP mode.
 

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I've had a great experience with Anker MFi product lines (made for iPhone), if you want to go the aftermarket route. For the other people using iOS products, you need to make sure the cable is able to handle the data and charger.
 

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I posted about the speed of the USB in the Ascent and learned that they are 3.0, but not the very latest and fastest. They still should do just fine. I agree, replace the cable. My son travels with one of those flat spare batteries that can charge the phone or charge itself through the vehicle and then be used to power or charge the phone.
 

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Anker or Monoprice MFI cables for me outside of the ones that come with our iPhones and Beats products.

I carry every new charger in the car just in case. Have 8 USB ports so why not ?

6 x lightning in various lengths
2 x microusb
1 x usb 3.0 to usb c

Have a 12v USB C PD outlet (30w) for my laptop and power hungry devices.
 
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