We have a dormant Acer Iconia Tab A-700. It’s a few years old, but as far as I know it hasn’t taken any physical damage. It doesn’t power on, and when the charger is plugged in, no lights activate. There were no symptoms (it didn’t power down suddenly; it just stopped turning on).
We tried other outlets, but only have one (proprietary ) charging cable to try. Is there any way I can test the cable (e.g. with a multimeter) or do I have to buy one, try it, and return it if it doesn’t work?
Other than staring at it, are there any troubleshooting steps I can take to narrow down the problem? Or once it’s bricked, that’s it?
Of course you can narrow it down. The problem is, when you open it up, you will be faced with a circuit board about the size of a stick of gum. To narrow the problem down, you would need to test voltages (mainly) from each subsystem. Start the the onboard power regulators. Move on to the internal battery and on/off switch. Etc. If you had the right microelectronics probes, and a schematic of the tablet, and you knew how to take it apart, you could narrow the problem down with binary searches in about 10 minutes.
That’s a lot of ifs. And an electronics tech who knows what they are doing is going to charge more per hour than the tablet costs new.
Habeed, I think the OP may be more interested in knowing if it is the charger, the charger cable, or the battery–because if it one of these three the OP can easily fix it. If it is something else it’s probably only worth it for a hobbyist to mess around with it.
Power supplies for this unit on ebay appear to use a standard micro-usb connector. Anyone you know with a standard android phone or tablet should have one of these you can borrow. These are easily and cheaply available as a power supply or USB–micro-usb cable and are not proprietary.
It’s not in front of me at the moment, but I’m pretty sure this isn’t a standard USB charger.
And PastTense is right–before I assume the whole thing is bricked, I’d like to be sure it’s not something simple like a bad charger or battery. Any way I can use a multimeter on the charger to see if it’s kaput? If it checks out and I can get to the battery, any way to check that?
Why don’t you take the battery out and measure the voltage? My thoughts are that if you do measure 3.7 volts then the tablet is probably bricked. If you don’t measure 3.7 volts then you need to do further research to find out if it is the charger or battery… Agree or disagree anyone?
Try other appliances with the charger - if they charge then it’s likely your tablet. See if you can closely look into the micro usb plug on the tablet for signs of wear or damage, it might’ve burned out and you need to replace that (a fairly common problem - or more common than I’d have thought - with Asus tablets).
If you’re electronically-minded you might be able to replace it (the usb plug) yourself, have a look for YouTube videos on damaged usb plugs, by ordering one online and replacing the old one with it. Videos I’ve seen show the usb plug on a strip of plastic that also connects to a nearby 3.5mm headphone socket, but I’m leaving it up to a phone/laptop repairer to deal with mine.
Apparently the Iconia tablet can be charged by standard 5V micro USB power adapters or cables if the unit is powered down and the screen is off. In that scenario it will slowly trickle charge but it takes 10 -24 hours to charge up at that slow pace. The custom 12V charger does it in few hours. So you can use a standard 5V micro usb charger to see if it will take a charge.
I want to strongly emphasize the xda-developers forums as the go-to place for help on a wide variety of Android phones and tablets.
In addition to what has been mentioned, sometimes a device just needs a really good reset. There’s usually some combination of button presses that does that. (And more to do a last-resort full factory restore.) The forums will help with that.
Some people find that if they get a really stuck tablet, the only way out is to unplug the battery for a day. But that requires opening it up (and putting it back together).
On the left (or right if you’re reading this on your head) is a regular micro USB plug that fits into most every other device we have.
On the right is the Acer plug. It’s close in size, but different enough such that a ‘regular’ USB cable doesn’t fit into the receptacle on the tablet.
It’s not pictured, but the mini USB plug doesn’t fit either.
Is it some sort of standard cable, one that I’m just not used to seeing? If so, what else uses them (in case we have one laying around and I’m just unaware)?
At a guess that little hump prevents the Iconia’s specialized 12V PS from being used on non-Iconia devices and blowing up non-12V compatible standard micro USB inputs. The linked thread above seems to indicate a standard micro USB plug without the hump will fit that Iconia input slot and looking at the pic I would guess that as well.
When say “USB” will not fit the Iconia slot are you talking mini USB or micro USB. It looks like a micro USB plug should fit.
As a reminder due to the fact that the Iconia has a 12V battery internally if you do use a standard micro USB charger (If it fits) it has to be used in trickle charge mode while the unit is fully powered down.
In looking at the ages involved the Iconia is now around 4 years old and that’s close to the max expected life for many smartphone and tablet device style batteries.