Hi all - I've had my G Tablet for 9 months or so; I quickly rooted it, applied VEGAn-TAB GingerEdition 7.1.0, and have been very pleased with the hardware in general.
Over time, I noticed the red, external indicator charge light began cutting in and out when I was charging and holding the G Tablet in bed. But I discovered that if I would lean the G Tablet against the wall, with the power socket pointing up, I could plug it in and the light was solid red and the unit would charge.
Well, NOW the unit is not charging at all although the external indicator light is red when I plug it in.
I'll leave it plugged in for days on end with the red light, but when I try to start the unit, it boots up to the unlock screen and then momentarily just shuts off. The battery indicator icon in the lower, right hand of the touch screen shows 0%. BUT the Charging indicator text on the lock screen shows "Charged".
I sprayed some contact cleaner on the connector; the red light indicator may be a LITTLE less flaky. I cleared the battery statistics in Clockwork Mod, I even opened up the unit, disconnected the battery for a bit, no change.
I am hoping for some external wisdom, put a fork in me, I'm done!
Thanks in advance for any input!
nitrams0 said:
Hi all - I've had my G Tablet for 9 months or so; I quickly rooted it, applied VEGAn-TAB GingerEdition 7.1.0, and have been very pleased with the hardware in general.
Over time, I noticed the red, external indicator charge light began cutting in and out when I was charging and holding the G Tablet in bed. But I discovered that if I would lean the G Tablet against the wall, with the power socket pointing up, I could plug it in and the light was solid red and the unit would charge.
Well, NOW the unit is not charging at all although the external indicator light is red when I plug it in.
I'll leave it plugged in for days on end with the red light, but when I try to start the unit, it boots up to the unlock screen and then momentarily just shuts off. The battery indicator icon in the lower, right hand of the touch screen shows 0%. BUT the Charging indicator text on the lock screen shows "Charged".
I sprayed some contact cleaner on the connector; the red light indicator may be a LITTLE less flaky. I cleared the battery statistics in Clockwork Mod, I even opened up the unit, disconnected the battery for a bit, no change.
I am hoping for some external wisdom, put a fork in me, I'm done!
Thanks in advance for any input!
Click to expand...
Click to collapse
Same thing happened to me. Lesson learned is to never handle the gtab while connected to the charger-the pin is too sensitive. If you want to keep running your gtab you'll have to buy a dock (like I did). Search for Malata/Gtab dock-should cost 40-50 bucks delivered
It should still be under warranty. You would want to NVFlash it back to stock, but they should be able to fix it if you send it in.
nitrams0 said:
Hi all - I've had my G Tablet for 9 months or so; I quickly rooted it, applied VEGAn-TAB GingerEdition 7.1.0, and have been very pleased with the hardware in general.
Over time, I noticed the red, external indicator charge light began cutting in and out when I was charging and holding the G Tablet in bed. But I discovered that if I would lean the G Tablet against the wall, with the power socket pointing up, I could plug it in and the light was solid red and the unit would charge.
Well, NOW the unit is not charging at all although the external indicator light is red when I plug it in.
I'll leave it plugged in for days on end with the red light, but when I try to start the unit, it boots up to the unlock screen and then momentarily just shuts off. The battery indicator icon in the lower, right hand of the touch screen shows 0%. BUT the Charging indicator text on the lock screen shows "Charged".
I sprayed some contact cleaner on the connector; the red light indicator may be a LITTLE less flaky. I cleared the battery statistics in Clockwork Mod, I even opened up the unit, disconnected the battery for a bit, no change.
I am hoping for some external wisdom, put a fork in me, I'm done!
Thanks in advance for any input!
Click to expand...
Click to collapse
Good news everyone...fixed.
I bit the bullet, opened the device up, and resoldered the power connector to the board. The device is charging now!
A few points to remember:
When plugged in, the device looks like it is charging...red indicator light is illuminated. So apparently electricity is flowing.
The whole board appears to be under soldered. I think this was the core issue for this incident.
The charged indicator on the lock screen was a red Herring.
Hope this proves helpful!
nitrams0 said:
Good news everyone...fixed.
I bit the bullet, opened the device up, and resoldered the power connector to the board. The device is charging now!
A few points to remember:
When plugged in, the device looks like it is charging...red indicator light is illuminated. So apparently electricity is flowing.
The whole board appears to be under soldered. I think this was the core issue for this incident.
The charged indicator on the lock screen was a red Herring.
Hope this proves helpful!
Click to expand...
Click to collapse
I'm experiencing the same thing. At first, I thought it was the power cord, so I bought a replacement, but that didn't fix it. So far, I've been able to get by through careful manipulation of the connector, but I know that sooner or later that won't work. I just bought a soldering kit so I could do this repair. Do you have any documentation you can share on what you did (other than how to open it, which I've got down)?
I tried soldering mine...no luck
I've experienced the same issues you described. I used to be able to charge my device when I maneuvered the power cord and tilted the tablet at the proper angle. However, 2 days ago I could not get any charge, no matter how much I moved things around. Today I decided to try and resolder the DC input jack back to the motherboard as others have described.
I opened up the unit and saw that the DC input was completely detached from the motherboard; it pretty much fell out when I opened the case. I wanted to resolder it back in place, however I could not get the motherboard out of the case. I unscrewed all of the six (or 8, I forget) mini screws, at which point I could lift the motherboard to about 30 degrees but I could not take it out. The various wire connections made me hesitant to remove it completely for fear of damaging things. The inability to completely remove the motherboard is problematic as the DC input (as well as everything else) is soldered to the other side of the board (facing down).
I tried to resolder anyway, but I ended up not having enough hands to hold the solder gun, solder, and the two parts to be soldered (motherboard and dc jack). I gave up and put the unit back together. I want/need to try this again, so does anybody have advice on how to do this? How do you completely remove the motherboard so you can have unrestricted access to the soldering side? I can't send the device to Viewsonic because it's been modded. Until I get this fixed, I can't charge.
As an alternative, should I buy a dock and forget about the DC input?
Thanks
nitrams0 said:
Good news everyone...fixed.
I bit the bullet, opened the device up, and resoldered the power connector to the board. The device is charging now!
A few points to remember:
When plugged in, the device looks like it is charging...red indicator light is illuminated. So apparently electricity is flowing.
The whole board appears to be under soldered. I think this was the core issue for this incident.
The charged indicator on the lock screen was a red Herring.
Hope this proves helpful!
Click to expand...
Click to collapse
I too, was hesitant about disconnecting the wires but I finally did it. Had to have a clear shot at the soldering pads.
As far as disassembly instructions go, I just removed all screws and connecting cables.
Note the position of the two longer screws on either side of the tablet dock port, as they are each threaded differently.
And be gentle with the cable connections. Good luck!
I gave it another go, this time I carefully disconnected the necessary wires. I cleaned up the the connections with some solder braid wire, resoldered it the DC jack in place, then superglued it to make sure it doesn't break off again. After reassembly, I plugged the tablet back in and success! It works and nothing is damaged. The only thing that seems to be off is the battery meter is always at 100%. I can deal with that .
eagleshead said:
I gave it another go, this time I carefully disconnected the necessary wires. I cleaned up the the connections with some solder braid wire, resoldered it the DC jack in place, then superglued it to make sure it doesn't break off again. After reassembly, I plugged the tablet back in and success! It works and nothing is damaged. The only thing that seems to be off is the battery meter is always at 100%. I can deal with that .
Click to expand...
Click to collapse
Is super glue flammable? Im not trying to be an a$$ but im just concerned that the heat of recharging it could put it back in a liquid state and possibly go up in flames or give off some harmful fumes.
Another success. And step by step procedure.
eagleshead said:
I gave it another go, this time I carefully disconnected the necessary wires. I cleaned up the the connections with some solder braid wire, resoldered it the DC jack in place, then superglued it to make sure it doesn't break off again. After reassembly, I plugged the tablet back in and success! It works and nothing is damaged. The only thing that seems to be off is the battery meter is always at 100%. I can deal with that .
Click to expand...
Click to collapse
Thanks for the info!
After reading about your issues, I decided to pop open the gTab and see what I could do. My gTab was able to charge but only when the cord was in a very particular position (cord wrapped around the outer edges of the device). Since it charges intermittently, I decided that it'd be good to pop open the case and see if I could fix the connection problems.
Disclaimer: If you're not comfortable with soldering, using a digital multimeter (DMM) or handling electrostatic discharge (ESD) sensitive components, I'd try to get someone who is. Please follow at your own risk. The instructions below will void your warranty. Good soldering skills are a must as you have to be careful not to leave cold solder joints, overheat nearby ICs, or leave gobs of solder. Be neat and clean!
Tools required:
Static free area to work with (conductive metal table tops are a no no!) If you have a grounding strap for your wrist even better!
Digital Multimeter (one with continuity and resistance testing)
Soldering Iron (hopefully one with high precision. I needed over 750 degrees F and a very fine tip to get the solder to adhere to the motherboard pad and DC input pin.
Solder (Good quality) I used the silver solder from Radio Shack.
Optional:
Helping Hands (to hold components together while you solder)
Hot Glue Gun (to hold components together while soldering if you don't have a pair of Helping Hands)
If you have a pin that's completely separated from the pad, or it's broken off, you might need bridge wire or some spare wire.
Solder sucker, or solder wick
LocTite
My steps:
Extracting the Motherboard
1. Remove the four corner screws underneath the rubber caps first!
2. Please watch the tear down video first before attempting as it has some good pointers regarding screws and cable (re)attachment. I found a good tear down video on YouTube (search for "gTab Tear Down") (I'm new to posting on here so I can't post links yet.) t3h_g3n3ra1 has a good post here too: http://forum.xda-developers.com/showthread.php?t=842354
3. Remove back cover as in the video. Don't pull too much as the tabs can break off. Work slowly!
4. Get rid of static now. Touch a grounded metal component. Use a static wrist strap if you can.
5. Remove the power cable first! (Don't throw away the blue tape as you'll be using it later to fasten it down when you reconnect the battery.
6. Remove all other the cables connecting the device to the motherboard (just the green section). You only need to remove the motherboard so you can easily get to the DC Input. You can leave all the other components connected to the chassis, battery and LCD in place. You shouldn't need to mess with these.
7. Unscrew the motherboard screws. Mind the screw placement because they're not all the same size. I used a piece of tape sticky side up and placed the screws in the relative position of their placement on the motherboard. You can also draw a rough diagram of the motherboard on the tape with a sharpie if you like. (You should be used to doing this if you've dealt with Apple products or if you mess with laptops regularly.)
8. Remove the motherboard and place it aside in a static free area (or static free bag).
9. Put the chassis and back cover aside.
Testing the solder joints on the motherboard.
If the DC Input just falls right out, I'll show you the pads that need to be resoldered. However in the my case where just the center pin was just not connected well, I'll give you the steps here.
1. First test the center pin. Hopefully I can post images and I can show you where to test. Using the DMM, test the center pin and the pad on the motherboard it should be connecting to. Out of the 5 pads that the DC input should be connected to, it's the only one off the center pin at the end. The other 4 connectors will be connecting to chassis ground. With your DMM probing the motherboard connection pad and the center pin in the housing, test for continuity and also test for resistance. On my model, continuity was intermittent showing that a connection was there, but not reliable. Testing for resistance, I was measuring a range from 0 to infinity, but it was mostly hanging above 400 ohms. For comparison, a good solder joint should show good continuity, with no breaking as well as < 10 ohms in resistance. With my measurements, I concluded that the center pin needed to be resoldered.
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2. Before jumping to the soldering gun, just for due diligence, you should test the 4 other ground connectors for connectivity and resistance. An easy way to do this is touch your first probe inside the DC input jack (by the center post, but do NOT touch the center post! It's like the game "Operation!" If you can't do this reliably, maybe you shouldn't try the soldering part.) The second probe should be touching one of the four pads on the motherboard where the 4 ground connections should connect. Test each individually. They should all show good connectivity (no breaks in sound, and little to no resistance. At this distance, your resistance really should be reading 0). If any of them shows a resistance > 10 ohms, you might want to think about resoldering.
3. If you can physically separate a joint, just leave it alone. Don't pick at it. It won't heal if you keep touching it! Wait until the soldering section!
Soldering
Note: This should be done for all the joints that you have identified as faulty in the previous section.
1. Use a fine or very fine tip on your soldering gun.
2. Heat your soldering gun to 750 or 800 degrees F. You could use less, but when I tested, I could stay on the pad or the part and the solder would NOT liquify. (Started at 600, then upped by 50 degrees until I got to 800).
3. Have the pad and the pin from the jack touching while you solder. Don't allow for gaps if you can. (optional) If you have a set of helping hands, use some plastic or rubber on the alligator clips so that they're non conductive. Have the clips hold the DC Input jack in place so you can solder the pads that have come loose. Sometimes you can use the hot glue gun to hold the jack in place while you solder. Sometimes easier than a set of helping hands. Just put a SMALL dab of hot glue on the opposite side of the jack from where you're soldering. Jut make sure it's out of the way. Note: if your jack has completely broken off, you may have to use a piece of bridge wire or spare wire to allow for a clean connection.
4. (Optional but usually good practice). Clean your connection. Remove old solder using a solder sucker or solder wick. If not cleaned you could be soldering on to a bad connection. There was so little solder on mine that I barely got any off with soldering wick.
5. Heat the parts your fusing. With the pin from the DC Input touching the pad on the motherboard, heat both together and then apply solder to insure a good connection. Failing to heat one part, could cause a cold solder joint. With the amount of force that your power cord puts on the connector, a bad mechanical connection will also cause the connection to become unreliable again.
6. Apply a small amount of solder to cover the pin from the DC Input to the motherboard pad. There should not be a giant bead of solder left over. Using too much solder you might accidentally fuse to some of the other connection pads that are very close to your joint.
Testing your soldering
As in the above testing section, retest all your connections, even ones you didn't solder! Often when working with surface mount components that are close together, people often create junctions that are not supposed to be fused.
1. Test the center pin for connectivity. Test continuity and resistance. Resistance should be < 10 ohms. The center pin should have excellent connectivity to the motherboard pad.
2. Test the center pin for non connection to grounding pads. With your probe on the center pin, test the 4 grounding pads for the DC Input. None of the grounding pads should show any connectivity to the center pin. If you used too much solder on the center pin, desolder it and resolder it again with just a connection to the motherboard pad.
3. Test the ground pin to the 4 ground pads. Put your probe in the DC Input sleeve (make sure to touch only the ground). Then put your other probe to the each of the 4 motherboard pads in succession. You should have good connectivity.
Reassembly
Note: Leave the power cord disconnected until everything else is attached and connected. If something explodes or smokes at this point don't say I didn't warn you.
1. Place the motherboard back in place.
2. Start placing the screws in the locations where they belong. Tighten each half-way only. When all screws are in, you can fully tighten them. If you want to use LocTite here, now's a good time. This is a mobile device after all.
3. Leaving the power cord until last, connect all the other cords and ribbon cables. Make sure they're connected.
4. Make sure the routing of the cables are in places that won't get bent beyond the bends they already have. Make sure nothing will stick out of the sides of the unit. The thin speaker cables are pretty bad and should be fastened down with a bit of tape.
5. Attach the power cable.
6. Double check all your cables and connections.
7. Keep the unit face down, otherwise the power and volume buttons could fall out. Turn the unit on. Should boot normally.
8. Using Spare parts battery information, Battery Spy, Battery Monitor or any other battery debugging app from the market monitor the battery.
9. Insert the DC Adapter. You should now show that the battery state is Charging (AC). If it's not then you may have another connection problem somewhere else. (beyond the scope of this article).
10. Replace the back cover.
Finish
In conclusion, the fix for my particular break was pretty easy and took about 40 minutes to actually perform (30 minutes testing, 10 minutes fixing). I know my method is quite conservative. I'm just trying to cover the largest audience with these instructions. I had shelved my gTab for a bit until I had time to do some research on how to fix the DC Input. My Xoom was fitting the bill for a while, but I felt the gTab needed some love. Now it's running solid, and with TeamDRH's beta of ICS, I just have some OS/Kernel tweaking ahead of me. I'm just excited that I can reliably power my gTab while testing ICS!
Hopefully you'll find this fix easy and helpful. Peer review or suggestions welcome. Thank you all for reading.
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Re: Superglue
kieso said:
Is super glue flammable? Im not trying to be an a$$ but im just concerned that the heat of recharging it could put it back in a liquid state and possibly go up in flames or give off some harmful fumes.
Click to expand...
Click to collapse
The superglue should be fine with the temperatures we're going to be encountering here. Now soldering the superglue directly, that'd be a bad thing. A dab of hot glue might work and would help cushion from shock a bit. I use it for our flight controller modules on remote control aircraft and the hot glue works just fine.
Same problems with my device. This thread is very helpful. I am going to attempt to tear down the device and solder the power connector pin today. I will update on any issues/problems i may have.
Update: With a $10 solder gun from radio shack and some persistence, my gtablet is back to life. After opening the device, it was evident that the power connector was the problem as if fell off the motherboard when I opened the case. I did not disconnect the wiring. I removed screws and was able to prop the mb at enough of an angle that I could maneuver the solder gun underneath and reattach the power connector. I was somewhat suprised/impressed when I put it all back together and it to powered up. Not that I doubted myself, but this was my first hardware repair on a tablet. My biggest challenge was after removing the screws, the clips were slightly challenging without the correct tool. I don't even know what the correct tool is for opening the 12 clips, but eventually I was able to get in.
This thread was a great help. Thank you.
I was also able to fix my gtab thanks to the walk through. Thank you.
Sent from my Transformer TF101 using xda premium
TL;DR: My phone, a Moto G7 Plus, only charges one way round on my USB-C-to-USB-C charger while the phone is on. When it is off it charges on both sides. It works on both sides of a USB-A-to-USB-C cable always. What is happening?!
My phone, a Moto G7 Plus, behaves very strangely. It will work in specific circumstances in inconsistent ways with a USB-C-to-USB-C (C-C) cable, but it will always work with a USB-A-to-USB-C (A-C) cable.
Imagine my C-C cable has two sides, A and B, which should both work (as it used to) since it is a reversible cable. When my phone is on, charging works on side A, but not side B. When I turn off my phone, it works on side A and B. If I turn on my phone with side B plugged in, it also works. But if I then unplug the charger and plug it back in on side B, it doesn't work. Sometimes charging with a C-C cable doesn't work at all unless I restart my phone.
My A-C cables all work on both sides.
If my phone works with A-C cables but not C-C cables, I guessed it was either a hardware problem. But if it's a hardware problem, the problem should be the same when the phone is off. Is it therefore a software problem? Is there a problem with the negotiation of power to the phone? Is one of the pins dirty? What on earth is happening?
I decided to clean my phone's port in case there was dust or dirt in the way interrupting the contacts. But this has not helped.
Ultimately I have done the following to diagnose the problem—and I am none the wiser.
Steps to resolve:
Removed lint from the port with a toothpick (obviously turning off the phone first)
Cleaned the port with rubbing alcohol and cotton wool (with the phone off).
Blasted the hole with compressed air.
Blasted the cable hole with compressed air.
Tried other A-C and C-C cables.
Bought a new 3.1 C-C cable.
Plugged the phone into a computer's USB-C port rather than a wall-charger.
Cleaned the contacts with a pin wrapped in alcohol-drenched cotton wool.
Does anyone have any insight into this very odd behaviour? I am stumped for troubleshooting.
UPDATE 28/10/2020, 12:55 p.m.:
Using an A-C cable, transferring data to computer only works on one side, but not another. Presumably a specific pin in the phone is faulty or dirty that is only used in a specific orientation.