Friday, 11 March 2016

Tesco Hudl2 battery problems and teardown - Part2

Following on from my previous post (Tesco Hudl2 battery problems and teardown) I ordered a replacement Li-Ion battery (from eBay) to compare and test if this was the problem.
The battery was identical to the original one I had (Apart from the screenprinting wasn't quite a clear, so I'm not sure if it was genuine or a chinese copy. Doesn't really matter!), and so the first thing I did was tested the voltages I was getting on the pins.
Again on the black and red wires I was getting around 3.9v which looked good. I then tested the yellow and green wires. As you may remember these were the two I was most interested in as I think they were 'sense' wires to the Hudl2 to perhaps control if it should power on, check for 'safe' state of the battery, etc.
These did the same as the original battery, same low voltage output and same floating values, however after a bit of thought I tried the test but against the red (positive) wires, and lo and behold I got values! I got the same 3.9v on both of these wires. Comparing to the old battery, that did the same, so now I know, both batteries are giving the same output.
Therefore I wasn't very hopeful at this making the Hudl2 work.
Connecting it up, and sure enough the Hudl2 wouldn't power on. Connecting the charger up it again didn't light the charge light. No luck.

I then took the main board out of the Hudl2 to look for any other signs of problems, couldn't find anything, many many probe pins are on the board underneath marked power, signal, etc, and probing almost all of these showed voltage and signal so the board was getting power, etc, and all looked OK, so it appears to be something a lot more fundamentally wrong with the board now.

My suspicion is that when the fault PSU/wire started shorting out the usb input, there wasn't enough protection on the board and it damaged some key components (Not just in the charge circuit/components) and effectively bricked the unit.

8 comments:

  1. Hi Andy

    If it helps, my Hudl2 just developed the same problem last week of seeming completely dead after being on charge overnight. No red light, not powering on despite various combinations of power button/volume up/volume down.

    With mine, voltage on red wires from battery to Hudl2 is 4.0V. Yellow wire is 0.3V. Green wire fluctuates between 0.2 and 0.3V every second. These figures are the same when it is connected to the USB charger and the same when not connected to charger.
    Have also bought another usb charging port off ebay but made no difference.

    I agree that it seems like a problem with the mainboard which could be tested by swapping a known working board perhaps from one off Ebay? That'll probably be my next option.

    Regards

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    Replies
    1. Thanks Woody, yes I agree something strange on the mbd. I've actually managed to get mine looked at by Tesco (Despite being over the warranty period) so might be worth you trying that too, I was willing to pay but so far they've said it'll be a free repair.
      When it comes back I'm curious to see what they've replaced (possibly everything!)

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  2. Replies
    1. Hi,
      Yes, interestingly Tesco took it away for service, and repaired it.
      Looking inside they replaced the battery (although it was new) and the motherboard. It's the fact they changed the motherboard that is curious, so whether something had failed on it, or if the failure condition causes it to 'shutdown' I'm unsure.

      But, it unfortunately doesn't help others out with similar situations since it appears to be a dead mbd.

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  3. We seem to have the same symptoms, and Tesco did agree to take a look. It was picked up on the 22 April, so hopefully they will fix it too. I assume you lost the installed apps? My son will be pleased to get it back but disappointed if his games data is lost.

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  4. We seem to have the same symptoms, and Tesco did agree to take a look. It was picked up on the 22 April, so hopefully they will fix it too. I assume you lost the installed apps? My son will be pleased to get it back but disappointed if his games data is lost.

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    Replies
    1. Yes, it was factory wiped, but if you use google play backup it should restore the apps (game saves unfortunately will be lost). Took them almost exactly 2 weeks to return it.
      Good luck!

      Delete
  5. It is the innovative product range and online compatibility that has earned Tesco a vast customer base and credibility across the globe. read more

    ReplyDelete