How to fix iPhone 4s error 29

I hope Replace 2 resistor inside battery c c problem solved tested solution

Try with genuine apple battery it will works fine and restore once again.

Hello,

This error as I could see is related to the power line of the board. To solve it you have some option;

1- Try to enter in recovery mode and reboot the device

2- Possibly the battery is not original so try to change the battery and re-plug in the iTunes

3- check the five capacitor in front the battery conector on the main board and see if they are healthy, if so, you have to solve it replace another one with microsoldering

4- check the battery conector and it's vicinity to see if everything is normal.

Hope to have helped anyone!

SOLON