Touchscreen not working with generic USB Charger!?

**digmys** · 06-07-2010, 10:25 AM

Looks like a similar issue plagues the incredible but I am coming from a Blackberry 9630 which also uses micro USB and NONE of my chargers either RIM or generic are working with the EVO. Well correction, they seem to be charging the phone, but the touchscreen is completely unresponsive making the phone unusable while plugged in.

Anyone experiencing anything similar with non-HTC chargers? Anyone know of a fairly cheap wall wart that has a long cable (> 4ft) or a micro usb cable (> 4ft) that will not have this issue for the office?

**MarqBland** · 06-07-2010, 10:28 AM

Hmmm...so I started a forum about my phone dying/resetting last night, and I didn't even think about that...the charger I had it plugged to is my "old" BB Tour charger. Previous nights was the OEM charger. I woke up to find a dead battery even though it said the phone was charging. So maybe the BB chargers don't put out enough power and make other things go crazy.

**slopokdave** · 06-07-2010, 10:29 AM

I read this on a review of a generic AC adapter someone was trying to use with a Droid.... he said it made his touchscreen all screwy. Weird.

**digmys** · 06-07-2010, 10:33 AM

Some of the incredible owners are saying they need a charger with at least a 1A (1000mA) whereas most generic and BB chargers are 500mA or less. But that doesn't make sense to me because I was under the assumption that all computers outputted 500mA to USB?

**skip259#CB** · 06-07-2010, 10:34 AM

I'm having the same issue. I brought a generic charger from target. The phone takes a while to charge and i'm unable to use the phone as the screen does not respond. I have to disconnect the phone from the charger when I want to respond to a message.

Seriously annoying. My BB would accept any usb charger, but my new evo won't charge with a generic mini-usb charger.

**digmys** · 06-07-2010, 10:37 AM

Any electrical engineer want to chime in? lol Or anyone know where to buy spare little HTC wall to usb converter things like it came with? Preferably for less than the $30-$40 I know sprint is going to be selling them for?

**ElCartelDR** · 06-07-2010, 10:43 AM

I too used a generic charger this weekend but it did not completely disable my touchscreen. When charging the home button would now open up navigation for some reason, that was my only issue.

My Pre used to be completely unresponsive when using a generic charger.

**tmac4life#CB** · 06-07-2010, 11:06 AM

I found the same issue. I haven't tried charging. Does it not charge? And anyone try a generic Ian charger?

**cbowen1997** · 06-07-2010, 11:24 AM

I have had a similar problem with my Droid. I don't have a car charger so I use my standard motorola wall charger paired with a power inverter that allows me to plug it in to the car. It charges fine but the touchscreen goes all wonky and is unusable while its plugged in. I'm not sure what the output of the inverter is.

**digmys** · 06-07-2010, 12:25 PM

I think the problem is that the phone actually uses more juice than generic chargers provide. One user reported his phone saying that it was dead but saying it was charging when left on a generic charger overnight. i know that i plan to find an appropriate charger and not risk shortening my batterys life span but i just dont know were to get such a charger on the cheap currently.

**blitz118** · 06-07-2010, 12:41 PM

I had the same problem with a charger I bought off eBay. It will charge the phone, but I cannot use the phone at the same time. I ordered another which allows charge and talk, but I have not received it yet. The generic car charge I bought off eBay lets me charge and talk. So you have to also look for the charge that allows charge and talk.

**DirkBelig** · 06-07-2010, 12:57 PM

I just tried the Monoprice 1A charger I bought for my Pre with my EVO this morning and had these issues. Double-tapping the Home button didn't give the Expose view, but caused it to stutter to the next screen over. Swiping down notifications were ignored and the clock screen opened. This can't be healthy for the hardware. Looks like I'm going to have to go back to slow charging off my PC's USB port.

OTOH, the included HTC wall charger, the charger from my Pre, and the Rocketfish car charger from my Pre all seem to work fine. Only the Monoprice charger is causing freakouts.

**Darth Mo** · 06-07-2010, 01:41 PM

Originally Posted by modplan

Any electrical engineer want to chime in? lol Or anyone know where to buy spare little HTC wall to usb converter things like it came with? Preferably for less than the $30-$40 I know sprint is going to be selling them for?

Best guess is that the voltage provided by the generic charger is off, most likely on the high side, which is throwing off the capacitive sensor.

Basically, the phone is charged up too high to sense the minute charge from your fingers.

**digmys** · 06-07-2010, 02:21 PM

Originally Posted by Darth Mo

Best guess is that the voltage provided by the generic charger is off, most likely on the high side, which is throwing off the capacitive sensor.

Basically, the phone is charged up too high to sense the minute charge from your fingers.

Ok, so that is actually the opposite of what I had originally guessed. Is anyone having any problems when connected by a generic USB cable to a COMPUTER? I don't HAVE to have a wall wart, I just need something 4ft+ so I can move the phone around my desk and am more than happy plugging it into the computer if I can just buy a 4-5ft micro USB cord. Not in the best signal area at my office (RTP, nothing but technology here, go figure) so the already weak battery drains super fast, im currently trying to baby it until 5pm.

**Darth Mo** · 06-07-2010, 02:34 PM

Originally Posted by modplan

Ok, so that is actually the opposite of what I had originally guessed. Is anyone having any problems when connected by a generic USB cable to a COMPUTER? I don't HAVE to have a wall wart, I just need something 4ft+ so I can move the phone around my desk and am more than happy plugging it into the computer if I can just buy a 4-5ft micro USB cord. Not in the best signal area at my office (RTP, nothing but technology here, go figure) so the already weak battery drains super fast, im currently trying to baby it until 5pm.

I have $0.99 USB cable from Hong Kong that I got off eBay and it won't charge the phone. The phone and PC recognize the connection initially, but it loses the connection after a few seconds.

However, I'm using a cable that came with my Canon camera and threw a micro adapter on it that works fine. So it doesn't have to be a HTC specific cable, just not generic or super cheap.

The generic cables are skimping somewhere, be it using lighter gauge wiring or cheaper wire, or the connectors/contacts aren't up to spec.

I can conduct some tests if I get a minute at work or when I get home to see what's actually going on. I'll go the cheap route if I know it's not going to be dangerous, but if it doesn't work I just usually leave it alone because I know there's a legitimate reason why.

**digmys** · 06-07-2010, 02:42 PM

Some tests would be GREAT!

**cdjh** · 06-07-2010, 02:59 PM

Originally Posted by ElCartelDR

I too used a generic charger this weekend but it did not completely disable my touchscreen. When charging the home button would now open up navigation for some reason, that was my only issue.

My Pre used to be completely unresponsive when using a generic charger.

I had this as well. I don't get why the home button would work but open the wrong screen?

**bucko21** · 06-07-2010, 03:15 PM

Is this happening with the Seidio chargers also?? If I buy an extra battery from Seidio I will get the charger from them too. I don' t want to waste the money on the charger if it will not work properly..

**digmys** · 06-07-2010, 03:46 PM

Originally Posted by bucko21

Is this happening with the Seidio chargers also?? If I buy an extra battery from Seidio I will get the charger from them too. I don' t want to waste the money on the charger if it will not work properly..

Not sure. I know that seidio always seemed to make quality products for blackberries and would assume that they did their homework here but who knows. What seems for certain is that if you buy a generic micro USB charger off eBay that says it is compatible with the EVO and other phones, the touchscreen will NOT work while charging and i think that it cant be good for your phone and/or battery in the long run.

**Darth Mo** · 06-08-2010, 09:25 AM

Sorry, didn't get home til late last night.

I stripped down the cable that doesn't work right and as I suspected, it's unshielded. Also, the data cables are untwisted, so there's no protection from EM interference. Interference along the cable is picking up is probably reaching the touch screen causing it to be either wonky or non-responsive altogether.

For those that are having this issue with a cable, check to see if it's grounded. If you don't want to cut it open, compare it to the cable included with the EVO. The unshielded cable will be noticeably more flexible when you bend it; it should be pretty obvious to tell the difference. If you can't tell the difference and are willing to sacrifice the cable buy cutting it, that will leave no doubt. I only have the one cable that didn't work, so I'm curious if any shielded cables are doing it too. That way we can identify that shielded cables are required and save some people headaches.

There's also the issue of pins 4 and 5, but that's much more difficult to test so I'd like more feedback on the cable shielding first.

Makes sense though. The copper and aluminum that goes into a cable shielding is the most expensive part of the cable. Stands to reason that a budget, generic cable would leave that out to keep cost down.

**yungwunn911** · 06-09-2010, 08:46 AM

Originally Posted by Darth Mo

Sorry, didn't get home til late last night.

I stripped down the cable that doesn't work right and as I suspected, it's unshielded. Also, the data cables are untwisted, so there's no protection from EM interference. Interference along the cable is picking up is probably reaching the touch screen causing it to be either wonky or non-responsive altogether.

For those that are having this issue with a cable, check to see if it's grounded. If you don't want to cut it open, compare it to the cable included with the EVO. The unshielded cable will be noticeably more flexible when you bend it; it should be pretty obvious to tell the difference. If you can't tell the difference and are willing to sacrifice the cable buy cutting it, that will leave no doubt. I only have the one cable that didn't work, so I'm curious if any shielded cables are doing it too. That way we can identify that shielded cables are required and save some people headaches.

There's also the issue of pins 4 and 5, but that's much more difficult to test so I'd like more feedback on the cable shielding first.

Makes sense though. The copper and aluminum that goes into a cable shielding is the most expensive part of the cable. Stands to reason that a budget, generic cable would leave that out to keep cost down.

will try my bb charger on my work computer to see what happens...Thanks for the info!!

**mikegoldnj** · 06-09-2010, 11:24 AM

No problems with the usb from my blackberry charging the EVO off the Mac USB.

**Darth Mo** · 06-09-2010, 11:34 AM

Originally Posted by mikegoldnj

No problems with the usb from my blackberry charging the EVO off the Mac USB.

I don't think anyone should have a problem with a branded or OEM cable included with another device.

It's the cables off eBay or a generic house brand from a store that are the ones in question.

**yungwunn911** · 06-09-2010, 11:59 AM

Originally Posted by mikegoldnj

No problems with the usb from my blackberry charging the EVO off the Mac USB.

I second this sans MAC. Running off of PC desktop.

However, plugging into my keyboard's USB gave me a "USB POWER EXCEEDED" error, had to plug diretly to the tower.

**SurplusGadgets** · 06-15-2010, 09:11 PM

The thread is awesome. I thought I was going crazy. So here is info based on refined testing directed by your comments above.

But first, my failure mode seems slightly different. The screen continues to operate normally. It is solely the four buttons on the bottom that fail. Sometimes all four. Sometimes only the home button. By fail, I mean hitting it does not cause an action. In all cases of failure though, hitting the home button causes the screen to flash but no action to occur. As a result, not sure if my results will be applicable to your problem -- is it the same problem?

After testing, it appears to be solely the connector, and not the amperage of the charger or shielding / quality of the cable. The HTC supplied charger is 1 Amp and its cable rated high speed with shielding. Higher and lower amp chargers as well as lesser quality cables (even simply a two wire charging-only cable) do not induce the problem for me.

Specifically, I have 8 micro- to mini-USB adapters. 4 of these 8 cause the buttons to fail consistently. The working 4 will allow any combination of cable and charger to be used behind it without exhibiting the failure. In fact, just plugging the adapters in, without any cable or charger attached to the other end of the 1" long unit, will replicate the failure pattern. That is, the same four cause the phone to fail just by the adapter being plugged into the phone whereas the other 4 allow the phone to operate whether a cable or charger is connected or not. So an unshielded cable does not seem to be the issue. It is in the connector somehow. Also, simply plugging in the bad adapter causes the screen to flash the same way it flashes when hitting the home button (a good adapter being plugged in and hitting buttons normally never causes the screen to flash and the home button causes an immediate and quick expected response).

Can provide details of testing but I have many different amperage wall charges, auto chargers, and cables. Most are mini-USB with only the HTC supplied cable being micro-USB in addition to my adapters. But I have many USB-outlet chargers and current sources that I could use on the HTC cable. I checked every combination of cabling, charger, and adapter and found nothing consistent other than the same four adapters inducing the problem. Even a 500 mA charger did not induce the button problem; nor a 2-wire, unshielded "power only" cable.

Note that USB standard only requires a USB HUB to provide 1 A maximum power (for up to 4 connectors). I think the maximum draw for any one device is supposed to be .5 A (or 500 mA) if I recall correctly. Most laptops and often desktops only have one hub powering the multiple external ports. A hub can have up to 8 connectors but I think the standard requires 1 Amp per 4 connectors. Most USB car charge docs I have found are 1 Amp minimum.

I recall the "car jack" mode where the EVO wants to keep on the "Navigation" app causing a similar flashing. (Have you seen how in car jack mode hitting the home button flashes the home screen before going to the Navigation app home panel. Similar to the bad behavior of the home button causing a flashing here it seems.) So one more test.

Went in and changed the default / fixed action for plugging in a USB cable to be "charge only". Tried the different combos of cables, chargers and adapters. Consistent failure mode only pointing to specific adapters.

So clearly there is some sensitivity in the USB port on the EVO 4G to the type of connector used; even if charge-only mode for the USB is on. The phone does not appear to be too amperage sensitive (at least for inducing this button problem). Look forward to your further refinements of these test results. Especially if you see similar model products inducing or not inducing the problem; or other adapters (without cables or chargers attached) inducing the problem.