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FP2 dead - red light on constantly?

Tags: #<Tag:0x00007f05e4a86498> #<Tag:0x00007f05e4a862e0> #<Tag:0x00007f05e4a860b0>

Hi,

I would really appreciate some help.

I finally had the awful accident of phone + water (drinking, not salt!)

The phone worked when removed, I shut it down and dried it out thoroughly (not for long, but in part by disassembling and physically drying it).

I started the phone - it worked. About 2-3 minutes later, I took a photo, (which I think worked) then the phone said the battery was flat and shut down.

Since then I have tried charging it. Initially the red charging light flickered on and off like crazy. Then the phone went through the on / Fairphone splash screen / off cycle. Finally the red charging light went steady. I thought I was sorted.

The phone has not charged since, and won’t turn on. Plugging it into anything displays a constant red LED (regardless of battery presence). It won’t even display the splash screen.

I have tried an old battery, and an old bottom module and top module - the same happens. Voltmeter across the +/- pins of the battery reads 4V.

I have taken the phone to bits (including removing the mainboard) several times. No joy.

Is this a dead main board? Why did it start before dying? If it is dead - is there ANY way to get my data off the board?

(Please avoid responses about drying out the phone - it has been 3 1/2 days since it last turned on - the phone has been left in pieces etc etc.)

I hope someone can help.

Thanks.

Edit: didn’t read carefully, missed the “regardless of battery presence”.

This does sound like a broken core module, possibly a short because of the water damage. Maybe there are #fairphoneangels near you with core modules that can be used for testing?

Hi rmf,

Thanks for your response. Unfortunately it is the same with or without the battery.

As soon as the cable is plugged in the red LED comes on. It stays on, but pressing any of the buttons makes no difference. So it doesn’t do as you say is expected - the phone just stays off, with the red LED on.

EDIT: rmf - no worries. I am going to try with a friend tomorrow - not a spare module, but if everything else in my phone works with theirs then I guess it must be the module.

Any way to extract the data from the eMMC?

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Not exactly run of the mill DIY stuff, sadly. There’s a thread about it here and I think the consensus is that it’s best to have it done professionally.

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Thanks rmf. Not what I would have liked to hear, but not unexpected!

I assume that FP don’t offer any sort of repair service (out of warranty) for this sort of thing? Data, rather than phone is more important

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If you take it apart do you see some residue or anything else that might look like water damage? If so you could try cleaning it with contact-alcohol.

Sounds to me like it wasn’t fully dry when you first started it and then a bit of moisture got to some part that is related to charging and caused (irreversible?) damage.

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Bring it to a (good!) repair shop and ask them to check the motherboard for damages. With some luck they just need to clean it.

Had the same accident with my tablet and they could save it.

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Hi Paula, Thanks for your message

Sadly, I can’t see anything that says “damaged” (apart from the red LCIs, as expected) It was clean water, so I guess it is unlikely to leave any residue.

I had come to the same conclusion after writing this. I think it must have been plugging it in to charge it that finally “did for it”.

I have managed today to meet with a kind friend and Fairphoner, and all my components work on their mainboard, and none of theirs work on my mainboard. So my conclusion is (unsurprisingly) the main board.


Thank you - definitely have hope here. However, I don’t suppose you know of any such places? I’m in Newcastle upon Tyne, England. I tried the main google result today (Tyne Tech), but after telling me that Fairphones are rubbish and not eco-friendly (missed the point there) and then saying that I was stupid, he said he couldn’t repair it anyway, because it might need a new mainboard building. So much for “not limited to water damage and PCB repairs”!!


Finally, I’m wondering whether anyone has any knowledge how to diagnose the fault on the mainboard? I’ve whittled it down to the board, but then there are various options in my mind. Given that nothing happens power-wise, until plugged in and then the light just comes on, I’m wondering whether it is the PMIC that’s gone? There seems to be relatively little that can short, so I’m just wondering how to find the problem. Maybe @Leo_TheCrafter can offer some knowledge?

Thanks everyone for your help!

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Recovering data from the eMMC wouldn’t be that hard if he had a datasheet. An eMMC is an embedded Multi Media Card, basicly an SD card, but it would require an expensive adapter PCB, which could easily cost a few 100€. I have worked on iphones with waterdamage before and know how to deal with these problems. Drying it doesn’t do anything, in fact you have the best chances of recovery when you bring the phone to a repair shop when it’s still wet.
If it dries it leaves nasty corrosion everywhere, causing shorts. Luckly most shorts aren’t that bad, as they commonly occur at capacitors between ground and VCCx.x.
As you describe the problem, the issue is somewhere in the PMIC section, as the LED still works, which indicates that the phone isn’t completely dead. I have high hopes for this device.
The standard procedure for this kind of issue is:

  • Take appart and rinse the board and the connectors with some 99% ethanol

  • Take off the shields with a hot air gun or if they are sticker shields, just peel them

  • Wash with ultrasonic cleaner for a maybe 1/2 an hour and immedialty rinse with ethanol again

  • Manually clean the board with ethanol under the microscope

  • If there are capacitors that are obviously damaged, take them off, most of them are decoupling capacitors that aren’t manditory, but can effect stability, but should be fine for data recovery, most of the times the phones work fine without them, if you really want you can replace them with some 1µF capacitors of the appropriate size.

  • If still not booting, you can check the capacitors and their resistance with an multimeter, everything over 50ohm is usually fine. If you have an short on the power rails, you can check if sth is a power rails by looking if it comes from an inductor, try searching for the faulty capacitor/corrosion.

It is common that some of the repaired waterdamaged phone have high battery drain, due to some smaller shorts still remaining, but for data recovery, not a problem, they might also be fully functional, who knows, it’s always a bit luck.
If none of this helps, you probably have sth blown up like PMIC or have some corrosion under the ICs and in the worst case some short destroyed the CPU, in these cases there’s nothing to do about it and the board goes to the pile of donor boards.
We don’t have schematics for the FP2, I hope we’ll get them one day, but it’s unlikely, because qualcomm likes to keep things confidential.

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Unfortunately this often is wrong guessing.
How clean is “clean water”? Do you mean distilled water or even ultra-pure water which often is used e.g. in semiconductor manufacturing processes?

Any normal clear water ready for drinking is not clean enough for any semiconductor or circuit-board to be rinsed with. There are minerals, salts, metals and other ingredients in it. Each of them increases conductivity which will cause short-circuits as you now have experienced.
If you feel like reading through these two threads: #waterdamage and #waterwiki . Maybe good for the future.

The treatment as @Leo_TheCrafter describes is thoroughly and maybe can get your board back to life. But as he writes, you will need some luck too.

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Sorry, I guess I’m not much help there.

You could take a look here:


I have done some online research as well, so none the better, than what you already tried. Still, some of the one’s I found are UK-wide active. So maybe…?

Leo, that is very helpful. Thank you for such a detailed reply. Do I take it, from your message, that this should really be the first step? Even before trying to identify exactly where the short is, or whether there is a dead IC? Unfortunately the shops I have contacted so far either say they don’t do phone PCBs or they don’t seem to do anything other than screen replacements!

Regarding eMMC recovery - I’m not keen as that is the end of the phone, but would be interested what you thought of this: https://dangerouspayload.com/2018/10/24/emmc-data-recovery-from-damaged-smartphone/

Thank you Patrick. Yes, I knew that if I stopped to think about it. I guess I was just meaning that it wasn’t the sea. But indeed it was not the handy bowl of distilled water that I keep around :wink: Thanks for referencing the water articles - although I was half aware, I thought it was dry enough, and had urgency to use the phone - retrospect is always easier! Hopefully there will not be a next time, but you never know!


@Paule and @BertG

Thank you for your pointers. I had found the link you attached, but obviously hadn’t read it properly. I will investigate further tomorrow.


Thanks everyone for your help. I will try to remember to update the thread when I have an outcome - whatever that be.

(I felt really sad to see the aforementioned repair shop in Newcastle already had a Fairphone with “the same problem” and that the owner had left it with not much hope. It sounds like there are a lot of more able people here and around the world.)

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The eMMC data recovery can apparently be done with the right tool, but that would only recover data, not repair the device.
Cleaning with 99% ethanol should always be the first step.
Having to solder is not always neccessary, had an iPhone 6 that worked after just some cleaning.

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Thanks Leo for the heads up. I do realise that it would be then end of the phone. I am only considering it as a last ditch attempt if the phone won’t work again.

I’m now trying to decide whether to send it in to a repair shop for this sort of thing or do it myself, accepting it may not work and a repair shop will then be necessary. Obviously I don’t have an ultrasonic cleaner, but otherwise is there much harm in trying with some ethanol (Isopropyl Alcohol) first, in your opinion.

Thanks for all your input - really appreciated.

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Really make sure that your solvent of choice is at least 99%, 80% is not acceptable and can ruin the device even more to the point that the demage is unrepairable

Thanks Leo. Appreciate you checking that I understood it must be the right strength.

The two options (if I do it myself) seem to be from RS Components (https://uk.rs-online.com/web/p/precision-cleaners-degreasers/2274427/) or CPC Farnell (https://cpc.farnell.com/electrolube/ipa01l/ipa-cleaning-solvent-1l/dp/SAIPA1L). Both are reputable electronics suppliers in the UK and the items seem to 99%+ IPA solvent.

I will probably give this a go as a ÂŁ10 attempt to fix. I have found a shop that is not too far away that supposedly does water damage repairs, so that is my next option. Will let people know here if I have any joy, so that they can (or not) get more trade :wink:

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Yes, you can also use q-tips to brush over heavily corroded areas.
Protip: If you sharpen a tootpick to a very sharp point, it can be used like a tiny brush to get inbetween capacitors and other components

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A little update…

I bought two IPA cleaners (one bottle, one aerosol) from RS Electronics.

  • RS PRO 1 L Tin Isopropyl Alcohol (IPA) for PCBs (Stock No. 227-4427) ÂŁ10.64 inc VAT
  • Ambersil 400 ml Aerosol Isopropyl Alcohol (IPA) (Stock No. 780-5225) ÂŁ11.09 inc VAT

I stripped down the phone to just the core module, removing the shields. For other users trying this, it is possible (with a very small screwdriver for example) to remove the shields on the front and back of the core module. They actually just clip on. You have to get between the large flat plate and the frame underneath. I will try to photograph it next time…! You do not have to peel the black graphite thermal sheet - (unlike the instructions in the iFixit tear down).

I bathed the main board in the IPA for a good hour, gently agitating it every so often. I then removed it with clean gloves and sprayed IPA from the aerosol into the various ICs, focussing on the PMIC. I dried the mainboard in the oven at 100 deg C for 30 minutes and then let it cool. I rebuilt the phone and it charged, and turned on.

That was Sunday. Yesterday (Monday) I managed to use it all evening (plugged in) and I got all the data off it. However there seemed to be a huge battery drain issue. I left it overnight doing nothing and this morning the unit is back to square one. Just a red light, no charging etc.

I will try recleaning it, but it may need an ultrasonic cleaner (I don’t have one) or more. If anyone has any good ideas then do let me know. At least part 1 of the mission is accomplished!


@Leo_TheCrafter - Would either of these cleaners be adequate for this sort of job? It is not something that I have ever needed before, so I can’t imagine using it a lot in the future, so don’t want to spend too much on a “hopeful” repair technique: https://www.amazon.co.uk/Ultrasonic-SKYMEN-Jewellery-Eyeglasses-Toothbrush/dp/B07H2DDM57 https://cpc.farnell.com/james-products/ultra-7000s/ultrasonic-cleaner-750ml/dp/SA03348 Is there anything I need to look for in a USS cleaner? I know that this isn’t heated, but then I can add warm water for the amount I’m doing.

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I wouldn’t reccomend buying an ultrasonic cleaner, If you have no other use.
Try cleaning with more IPA and use toothpicks and Qtips.
Try to shake the board in the IPA, so that the IPA gets under the ICs.
It is also common that waterdamaged phones have a wrecked battery.
Maybe a fairphone agle can lend you a known good battery.
I had a “waterproof” camera , which got wet with seawater, which destroyed the battery to the point that it wouldn’t even turn on. If the short was somewhere, like VCC_Main, Which is essentially, the battery (Terminology from IPhone, happens very commonly on them, but every phone got such a power rail, sometimes also known as SYS or Main, can be identified by it’s voltage range of 3.6-4.2V or it’s connection to the Charger/PMIC) could drain completely, destroing it.

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