Why has my Samsung Galaxy S4 Qi stopped working?

[AC Question]

Samsung Galaxy S4 Qi stopped working

I just purchased a wireless charge pad with receiving coil. Installed coil and plugged USB cable from pad to a 2A wall adaptor.
Phone recognoized wireless charging right away and charged from 30% to 60% and stopped... now discharging.
I removed coild and inspected connecting tabs - all seems well here.. I added a small piece of tape to secure connection better but phone still not seeing and charge.
I removed the receiver coil and placed it on the charge pad and the voltage across the contacts is about 5.1 V so the pad and coild appear to be working, but the phone circuit is not seeing the charging voltage on the Qi contacts.
Any ideas?

 

[Rukbat]

Re: Samsung Galaxy S4 Qi stopped working

I was going to suggest taping the coil to the phone (not the battery), but you've done that. Try wiping the contacts on the phone and on the coil with a coarse cloth - even gauze from a Band Aid is coarse enough. Then make sure you feel the contacts slipping into place before putting the tape on. Turn the phone off and see if it starts charging. (A rogue app or a bad SD card could be drawing so much current that the 640mA you're probably getting from the Qi receiver (use Galaxy Charging Current Lite to see how much current you get, once you get it working) isn't enough to charge the battery. (If the phone is drawing 700mA, 640 of it is coming from the Qi receiver and 60 is coming from the battery, so even though you have a charger running, the battery is discharging.)