Smartphone in water and touch screen not working. - Page 1
Forum section: electronics / general

author: hanndoddi
author_rank: Contributor
timestamp: January 12, 2014, 11:18:59 pm
content: Hello every one.I have a case were a smartphone fell in to a cleaning bucket. After it happened the battery got taken out and the phone was dried.Now it starts up fine and every thing looks good, except the touch screen it not working.Does any one know what is causing this and how to fix it?

author: rolandpenplotter
author_rank: Regular Contributor
timestamp: January 12, 2014, 11:36:35 pm
content: Quote from: hanndoddi on January 12, 2014, 11:18:59 pmTry gsm forums; also, its almost impossible to diagnose such things without seeing the item, since its not a "known fault" - anything could be faulty or damaged.http://forum.gsmhosting.com

author: Psi
author_rank: Super Contributor
timestamp: January 12, 2014, 11:46:30 pm
content: Water inside the touchscreen is probably being interpreted as constant touch presses and the touch driver is failing initialization.You really need to take phones completely apart, dry and clean them once they've been submerged in water. Sometimes they do work with a quick dry on the outside but as the water evaporates it leaves behind residue which will corrode and damage the pcb over time.Usually things not cleaned and still working will start to fail 6months to a year after the water got inside.I would take it apart as much as possible, i don't remove anything that maybe hard to get back together like the metal can shields on the pcb. No point trying to fix it if it gets damaged trying to reassemble.Give everything electronic a good wash with iso but be careful of anything that may not like solvent getting inside, like speaker/mic.Put all the bits in a oven safe dish and stick it into the kitchen oven at ~50degC.50C is enough to evaporate all the water out without any damage to the electronics or plastic.I leave it in the oven for 4 hours or so, then remove and clean the boards with pcb spray/flux remover or iso and let sit to dry at room temp. Then reassemble.

author: hanndoddi
author_rank: Contributor
timestamp: January 12, 2014, 11:59:33 pm
content: I understand.Thank you for a fast response rolandpenplotter and Psihttps://www.eevblog.com/forum/Smileys/default/icon_smile_thumbsup.gif

author: peter.mitchell
author_rank: Super Contributor
timestamp: January 13, 2014, 04:08:50 am
content: I'd not use it for any period of time if the touchscreen isn't working; the possibility of water/moisture being still present and the battery connected will promote corrosion.Take the battery out, disassemble as far as practically possible, submerge in isopropyl alcohol, "dunk" it a few times, you want to try remove all trace contaminants, eg minerals, and water.After it has been "washed", let it dry at ambient, until no trace of isopropyl is visible, this should be quick.Then do Psi's bake method. But be careful, don't do it in a gas oven, don't place it close to elements, make sure its on a tray, make sure it isn't resting on any plastic parts, you might want to raise it up off the tray a little with some spacers.

author: Psi
author_rank: Super Contributor
timestamp: January 13, 2014, 06:45:12 am
content: Thanks yeah, I forgot to mention the iso wash first.If its an old convection oven then shielding it from the heating element is a good plan.For fan ovens put it into a dish so the fan can't blow anything around.

author: amyk
author_rank: Super Contributor
timestamp: January 13, 2014, 07:59:23 am
content: Quote from: Psi on January 12, 2014, 11:46:30 pmDo most ovens even go that low, since they're usually built for much higher temperatures? I'd also think the control loop wouldn't be so stable working at that range.

author: Psi
author_rank: Super Contributor
timestamp: January 13, 2014, 08:52:23 am
content: All the ovens i've used have a temp dial which goes from zero to ~250CFruit cake is often baked at ~80C for many hours, and theres a few other legit food uses for low temps, like making dough rise.

author: hanndoddi
author_rank: Contributor
timestamp: January 17, 2014, 10:41:54 pm
content: Phone now works!https://www.eevblog.com/forum/Smileys/default/icon_smile_thumbsup.gifIt got taken apart and put in a oven on 50° for 60 minutes and is just like new now.Thank you very much for all the good info.

author: rolandpenplotter
author_rank: Regular Contributor
timestamp: January 18, 2014, 12:07:29 am
content: Quote from: hanndoddi on January 17, 2014, 10:41:54 pmWell doneBy the way; if you want a smiley, either type ": )" (no space or quotes) or get the smiley GIF's URL, and put it between tags.

author: Radio Tech
author_rank: Frequent Contributor
timestamp: January 18, 2014, 11:48:42 am
content: I had a phone that was dropped in water. After a good cleaning it would power up and then turn it self off.Disassembled again and put phone in a zip lok bag filled with dry instant rice. 2 days later works like a charm.

author: HackedFridgeMagnet
author_rank: Super Contributor
timestamp: January 18, 2014, 12:08:47 pm
content: Must've been hungry.

author: Psi
author_rank: Super Contributor
timestamp: January 18, 2014, 12:40:44 pm
content: You could probably use cinnamon instead of rice for a faster drying time.Phone would smell nicer too, but you'd probably end up cursing the desire to eat cinnamon buns every time you get a call