Xperia SP Did i blew up the charging circuit ? - Page 1
Forum section: electronics / beginners

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: May 24, 2014, 06:34:54 am
content: Hello peopletoday i tried charging my phone using a 5 V 2Amp rail on a pcb from a monitor!.I connected the usb and shorted the ground and Data + pins on the usb connector to start the charging.The phone was charging but the battery dropped form 70 to 69 % after this i disconected the phone and rebooted it the battery was 93%.Then i pluged the phone to a 1.2 A charger that i was originally using (Not the charger that came with it! this was a Nokia charger) and the phone would not charge.After a reboot i saw a meesage that one app got uninstalled.Now the phone works fine and its charges (kernel detects charger but pc will not)Anyway i took a look inside to see if anything was blown and i did not find anything strange.I dont know if this is a hardware of software thing anymore this is why i posted the thing here because at XDA developers forum everyone is hardwarephobic........

author: rexxar
author_rank: Frequent Contributor
timestamp: May 24, 2014, 07:29:22 am
content: First you shouldn't short the D+/- lines to ground. The Dedicated Charging Port spec is D+/- shorted, and no connection to 5V or Gnd (at least in the documents I've found).I hate to state the obvious, but it has to be asked: are you sure you got the pinout right? You didn't accidentally switch 5V and Gnd, or connect your data lines to 5V, did you? If your PC doesn't recognize your phone at all, it does sound like you damaged the USB circuitry on the phone.The note about an app being uninstalled is probably entirely coincidence. Though, for peace of mind, I'd try restoring a nandroid backup (you do make those regularly, right?) from a few days ago and see what happens with your computer.In my experience, phones willsaythey're charging if they see 5V on the USB port. The charge IC may have died, so it won't charge the battery, but the rest of the system still sees the 5V there. I'm not sure what kind of charge controller they're using, but it might be of the kind that directly interfaces with the USB data lines for charger type sensing. These usually connect straight to the USB port, and when they've detected what kind of charger you've plugged in, they turn the USB data lines over to the main processor.If you've killed that chip, maybe by connecting D+/- to 5V (or more), it won't switch data over to the processor, so your computer can't see it anymore.

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: May 24, 2014, 11:47:53 am
content: Quote from: rexxar on May 24, 2014, 07:29:22 amI am sure about the pinout of the usb....Quote from: rexxar on May 24, 2014, 07:29:22 amAbout that..... i was not keeping backed up files...I had all my apps backed up using Titanium Backup but as for the Rom i did not have any problems because i could just restore my apps anytime with data.So yeah .... i tried formating /system and factory reseting the phone so i could flash another rom on top to compensate for the uninstalled app but i could not get access to recovery.Quote from: rexxar on May 24, 2014, 07:29:22 amThats the thing now.The phone if connected to a charger (or PC) charges boots up and charges normally so the kernel part that detects the 5V signal works fine.BUT now i think about it i may screwed up big time when i shorted the Data + to Gnd because the data lines must be dead thus the PC is ignoring the phone.

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: May 24, 2014, 11:53:32 am
content: Another thing is i went today to a service store and the guy said it would be 9 Euros for the shipping to the main service center and that he would send it labeled as warranty not void but he said that they probably will know that it has been opened by the broken wax seal.Adding to that i would not like to pay like 100 Euro just to get it fixed but is there any way to "seal" the screws again ?Also i have a damaged screw from the device because i could not unscrew it easily.So if i get replacement screws to make it look like new and "seal" somehow the wax it could be serviced for free dont you think ?

author: Bored@Work
author_rank: Super Contributor
timestamp: May 24, 2014, 02:08:12 pm
content: Quote from: ChrisGreece52 on May 24, 2014, 11:53:32 amSo you want to do a warranty claim for damage that you caused yourself by abusing the USB port? In my neck of the wood this is called fraud.

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: May 24, 2014, 02:35:49 pm
content: That IS fraud and i am not proud for even thinking of it as a solution.But i cant afford to pay 100 Euro just to fix the damage. If the phone can be repaired for about 60 or 50 i would most likely pay to fix the damage but i can not afford 100 at this point.If i had a replacement phone i would gladly wait to gather up the money but i need it fixed ASAP.Although the fraud plan is not cheap either (it would cost about 50( screws and the shipping alone cost 30 Eur + 9 for the shipping to the service center))I will send the phone to get an estimation about the damage cost and ill see what i will do.I know the moral thing to do is to pay the whole repair my self and i would if i could afford it.