Have a slightly different problem. 1 out of 4 handset is forever charging even though battery is full. I can put a known full battery (shows full in other handsets) into this one and it will show 1 bar. If the handset charging circuit think battery is not full. All of this without the charging station. The charging station is fine as I can put other good handset in there and battery charing behavior is correct (shows charge complete when full) So obviously if the handset thinks a full battery is not full, then its always charging and generating heat like what I am seeing. Going to probe the circuit board (pic below) for voltage readings. Looks like there are diode on the battery side also. Wondering if others have had this problem. I have 4 handsets and using a known good fully charged battery, I get 2 handsets showing 1/3 bars, 1 showing 2/3 bars, and only 1 handset showing 3/3 bars. Dug a bit deeper into the schematic (didn’t find exact but perhaps close) Battery voltage is fed to the IC (likely pin 58...
Just did this repair on iPhone 6 no boot after water damage, ran fine after, put in rice for awhile, powered on, screen flash squiggly lines and no boot (All done by relatives of a friend haha) Opened it up and took out logic board (need to track screws carefully (get a rubber mat to put them on so they don’t easily get bounced around), if wrong longer screw goes into the hole (particular the lower 3 LCD EMI cover screws) it will damage the circuit board, its called long screw damage if you want to search for that) and found the frequently burnt out capacitor (C5202_RF) on water damaged iPhone 6/6+. Failed cap created a short on the power rails to the wifi chip. Had a cell phone repair shop remove this cap and phone is fully function. Cap doesn’t need to be replaced since its just condition the power source for lower noise for the wifi chip power supply. Not really necessary. I also gave the logic board an alcohol bath for good measures. Didn’t have an ultrasonic cleaner for a more thorough cleaning so 99%...
I know the $25-$30 ones from ebay and tmart.com has a lot of quality problems. Out of the 4 I tried (2 from ebay sellers, 2 from tmart), the 2 from ebay failed within a day or two. One of them has a poorly manufactured connector. The 2 from tmart.com has very poor viewing angles. Color would become psychedelic with a slight tilt. I didn't have problem with a $20 new iPhone 4 LCD from ebay seller 2 years ago. But this recent purchase of $25 iPhone 4S LCDs showed a lot of problems. Certainly, the appearance of the quality seems high with the naked eye. But I could see the subtle defects in the LCD connectors under the magnifying glass that would not provide a proper contact. The LCD viewing angle problems is likely in the materials and/or assembly of the LCD itself. Anyhow, low priced aftermarkets seems to be hit and miss depending on the materials and manufacturing quality of the particular batch.
Had a problem where toothbrush would shut off right after turning on. Turns out the tab on the positive electrode had came loose. I tried soldering but the tab would not take on any solder (probably should have sanded the surface first). Finally just used a copper wire instead of the tab and fully functional after soldering.
Note sanding the battery electrode surface greatly helps solder to stick.
Had a problem where toothbrush would shut off right after turning on. Turns out the tab on the positive electrode had came loose. I tried soldering but the tab would not take on any solder (probably should have sanded the surface first). Finally just used a copper wire instead of the tab and fully functional after soldering.
Note sanding the battery electrode surface greatly helps solder to stick.