RX TX CHINA MOBILES

Method 1: HOW TO FIND RX TX It is tasted and also you can test it. 1 step is, we need to find GND from phone. 2 step is, we should power on phone (operation with dead phone: phone must be 100% dead by software)and take multimater put it to voltage. 3 multimeter (-) line put it GND and with (+) line check each connectors , and usually Tx= 1.8v or 2.8v and Rx=1.7v or 2.7v (it will be change by processor but strongly 1.7v or 2.8v not 3v or 4v) This way is too easy and you will save a more time. Method 2: How To Find Rx,Tx "The Multimeter Method" 1. Plug your new connector into your phone, with solder pads/pins exposed 2. Put Multimeter into fault-check. (or if unavailable, then it’s highest resistance range) 3. Keep negative Multimeter probe on negative battery connector in phone. 4. Touch each pin of the connector in sequence with the other probe until you hear a beep ( or see 0.000 resistance ) 5. Note this connector pin as GNDPin 6. Now install battery and switch on Phone 7. Put Multimeter into DC voltage measurement 8. Keep negative Multimeter probe on GNDPin 9. Touch other pins of the connector in sequence and note pins that have voltage between 2.6 and 2.9 volts.(be careful not to short pins ) 10. You should end up with a list of 2 or 3 pins. RX and TX will be among these. 11. Try all combinations of RX and TX with these pins you found. I’ve found several hundred pinouts with the method above. It works 99% of the time, and takes about 2 minutes once you’re in practice. So you now have your RX, TX, GND wires on your interface end, and your pinout or set of pinouts to try for the phone.