Troubleshooting guide for Nokia 300 touch screen issue
Problem: Touch screen not working, Touch is ok but problem occurred.
Solution: Heat touch ic, Change touch ic, Remove and make jumpers.
In this condition you have try every trick. Change with new touch. The touch is ok but problem still and touch screen not working.
This problem comes with due to water of old handset. The real issue of this problem. The touch screen did not work. Touch screen connector points are show perfectly at check meter.
- Check The touch screen first. To checking the touch screen. There are four pins. At the probe two by two connections are ok. 1x4 and 2x3 are the show with polarity. Now attach meter probe with 1x2 points of touch side connector. Push your finger on the touch front. If there is some polarity showing on the check meter. This mean touch rx is working. Same test repeat with other two pins. The polarity is showing. The touch is working very well.
- Heat the touch ic. To trace the touch location on the motherboard. Please see above image here. The touch place is showing without touch ic by jumpering. Be careful by heating you have experience for that job.
- There is no luck and touch ic connections are missing. The final solution is remove touch ic and make jumper directly with jumper wire. The jumper diagram is given in the above image here.
- For the jumpering you need very sharp bit. I recomend you please use the heat gun iron with the voltage regulator.
- Almost done!