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Author Topic: Help me rescue my Dingoo  (Read 788 times)

Offline sad guy

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Help me rescue my Dingoo
« on: June 17, 2012, 02:25:57 PM »
Hello, long time lurker here.  ;D

I got an old ILI9325 Dingoo for a few years already. I lent it a friend for a few days and guess what, broken...
He said it worked in the evening, then on the morning connected it to his pc to charge and load some roms, then discovered the fault later. So it must've happened when connected to the pc, maybe a dodgy cable or so.

It does nothing right now, only sits there with the black screen staring into my soul. I had a short dingux screen once when connecting USB but it disappeared after a half second. Nothing since then.

Opened it and had a look, everything looks great inside beside some dirt. Checked with a multimeter if the USB port gets power when connected (it does), if the battery is connected (it is) and some resistors or whatever. Total electronics noob here...

Edited a lent pic from dingoo scene to show what i measured where:



As you see 3.7V everywhere I checked except in the upper right black box (lol told you i'm a noob), where only 0.2V are measured. Now i wonder, is that normal or not? The solderpoint is quite big too on the right side of that thing. Oh and before i forget, reset gives me 2.3 V and Power has 3.3V.

Has my Dingoo a chance to survive this?  :'(

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Offline sad guy

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Re: Help me rescue my Dingoo
« Reply #1 on: June 17, 2012, 05:11:45 PM »
Sorry for the double post but i made a "discovery" when checking some more with the voltmeter. I measured the left silver long thing (Y2) and the Dingoo turned on all of a sudden but got stuck on the Dingoo screen or in the menu. Measuring while being connected to USB makes my PC recognize the Dingoo. I also got the USB screen.  ;D

Still clueless how to fix it though lol... letting it charge now to be sure. Hints are very welcome.   :)

Edit: So i pressed reset while being on USB (hoping it would boot into the menu) and it just shut off. Switched it on again with that "trick" and it gets stuck in the menu again, showing 2 power bars instead of 0 now... 

Good thing is i now know it's neither the LCD nor the battery... Could a corrupted flash cause such a thing? I remember having some write errors. I'll try the unbricker i guess.

Edit2: I even get the Dingoo into USB mode that way, but the driver doesn't work on Win 7 x64. Will try tomorrow.

E3: Even managed to boot into Dingux doing this trick. Makes me glad to see my Dingoo working, although it's unusable open like that. That long silver thing i short seems to activate the backlight btw.
« Last Edit: June 17, 2012, 06:06:48 PM by sad guy »
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Offline K-77

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Re: Help me rescue my Dingoo
« Reply #2 on: June 17, 2012, 06:12:31 PM »
make chkdsk on internal memory and the memory card.

Good Luck!

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Offline sad guy

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Re: Help me rescue my Dingoo
« Reply #3 on: June 17, 2012, 06:31:56 PM »
Good call on chkdsk! Tried it and it found the corrupt file i deleted some time ago. Some bad sectors in the end of the 4gb, nothing too bad i guess as it did work with those errors. Thanks for the hint (and the wishes)!

But i have made progress: Turns out the Dingoo works fine just without backlight! Shorting that long silver thingy activates the backlight and "fetches the last pic out of the framebuffer". Keeping it shorted with a screwdriver, my Dingoo seems to work just as it should!

The green thing:


So if your Dingoo has similar symptoms (black screen, NO clicking speakers), try that! I'll try keeping the wires of that thing shorted and see if that helps.

Edit: Or could it be the silver thingy simply died and could/should be shorted? No idea what it does/did anyway... xD

Another edit just incase it might help or interest someone sometime somewhere:
In Dingux, the thing does not need to be shorted to see movement, it is only "required" once each time when the backlight changes. In Native it must be constantly shorted to see movement. Thought that was interesting.

But since the Dingoo does not get recognized by my pc at all if i don't short that thing it seems that thing is quite important... Anyone knows what it is and does? :D

I'll try permanently shorting both points with wire and see how that goes.  :o
« Last Edit: June 17, 2012, 06:50:33 PM by sad guy »
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Offline K-77

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Re: Help me rescue my Dingoo
« Reply #4 on: June 17, 2012, 07:09:21 PM »
Hmm, I'm not an eagle in electronic but it looks like capacitor.

And yes it's probably dead.

I assume he died protecting other some more expensive parts, so i don't know if shorting the wires is good idea.
« Last Edit: June 17, 2012, 07:35:08 PM by kowkar77 »
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Offline sad guy

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Re: Help me rescue my Dingoo
« Reply #5 on: June 17, 2012, 11:09:26 PM »
I see. Too bad the capacitor is not labeled...   ???

Can i measure the other same looking capacitor with the multimeter and identify it's properties that way? If so, how? Just check the voltage when on? ^^

Edit: OK i found a formula to measure the capacity but it's a bit over my head... If someone knows what kind of capacitor this is i'd be extremely grateful.
Or i'll remove it and ask at an electronics dealer, but i fear he won't know the kind of capacitor without any label...

Oh and it seems to have indeed leaked, i see a bit yellow crusty stuff on the top of the cap and on the board below it.

Wait, that's glue. xD
« Last Edit: June 18, 2012, 12:12:35 PM by sad guy »
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Offline sad guy

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Re: Help me rescue my Dingoo
« Reply #6 on: June 18, 2012, 01:54:38 PM »
Sorry for double post again  ;D

I wonder how those chinese factory workers find out, which leg of the cap is the minus one... No indication on it at all. oO

Edit: Just googled Y2 capacitor and it seems Y2 is part of a cap class called suppression capacitors. Not sure if the Y2 (and Y4) written on the mainboard are telling anything about the caps at all. Probably not.

I'll try resoldering the cap (maybe the solder point broke), if that doesn't help i'll try to find an equivalent.
« Last Edit: June 18, 2012, 02:10:20 PM by sad guy »
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Offline K-77

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Re: Help me rescue my Dingoo
« Reply #7 on: June 18, 2012, 01:58:36 PM »
Ok so you have an expert here (Darth) I'm sure he gonna help you better than me ;)

Regards.
« Last Edit: June 18, 2012, 02:14:15 PM by kowkar77 »
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Offline darth_llamah

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Re: Help me rescue my Dingoo
« Reply #8 on: June 18, 2012, 02:05:43 PM »
a) this is not a capacitor,this is xtal (crystal resonator)- required for clock generator
b) if you short it's legs clock generator won't work (and dingoo will be "dead")
c) if one of legs is broken- clock generator won't work

d) capacitors do have + and - except the smallest ones (in terms of capacity, not size)
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Offline sad guy

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Re: Help me rescue my Dingoo
« Reply #9 on: June 18, 2012, 02:19:59 PM »
Yeah, caps have + and - , googled quite a bit this night. Still big thanks kowkar for your hints. :D

Thanks for the hint darth llamah, more to google.  ;)
I shorted it's legs quite often already though and so far it still kinda works. Right now the Dingoo is connected to the PC charging, switched on by shorting the legs of that bad boy (before i read your post ofcourse...).

Who knows in what crazy way the xtal is used in the Dingoo.  :)

Edit: OK, so it seems the Frequency of the CPU or whatever is controlled by this. So without the right one the Dingoo will go all messy lol. So without the exact part number i'm out of luck on replacing it. Let's hope it still works.

Just noticed that it is enough to touch the below solderpoint with a screwdriver, resoldering is probably my safest bet. Too bad i'm a noob at soldering and my iron is huge. Man i love challenges. ;D
« Last Edit: June 18, 2012, 02:30:11 PM by sad guy »
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Offline darth_llamah

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Re: Help me rescue my Dingoo
« Reply #10 on: June 18, 2012, 02:25:36 PM »
Quote from: sad guy on June 18, 2012, 02:19:59 PM
Who knows in what crazy way the xtal is used in the Dingoo.  :)
Only clock generator uses it, unfortunately I don't know what is it's frequency (with such thin legs there is a high chance of breaking them by accident)
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Offline sad guy

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Re: Help me rescue my Dingoo
« Reply #11 on: June 18, 2012, 02:32:14 PM »
Yeh i thought that i'd need the exact frequency too (hence my edit above ^^). But it seems to work at least, or my Dingoo wouldn't do anything, right? Lending a smaller iron from a friend and will resolder it tonight.

Huge thanks!

Edit: Guess it's a T6 or T8 one? Should other packages theoretically work too (if they have the right frequency)?
http://en.wikipedia.org/wiki/File:Crystal_Packages.jpg
« Last Edit: June 18, 2012, 02:43:26 PM by sad guy »
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Offline darth_llamah

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Re: Help me rescue my Dingoo
« Reply #12 on: June 18, 2012, 03:12:17 PM »
It's a T6 package.
And yes, xtals working on the same frequency should work good.
As for the frequency- maybe mth, Ayla or zear know which xtal is used
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