IPhone XS Max mobile phone screen does not show fault repair

IPhone XS Max mobile phone screen does not show fault repair.

IPhone XS Max mobile phone screen is not displayed, and it is found that the resistance of PMU_TO_DISPLAY_RESET_CONN_L line at pin 5 of the cradle is unstable. Scrape the PCB board, reconnect the lead of PMU_TO_DISPLAY_RESET_CONN_L, and repair the fault.

Machine model: iPhone XS Max mobile phone

Fault phenomenon: the screen of the mobile phone does not display intermittently.

Test results: the functions of the mobile phone are normal, but the screen will be discontinuous and not displayed.

Fault analysis: the fault should be caused by the abnormal line connected to the display seat.

Maintenance process:

Replace the screen test first, and after the test, it is found that the fault has not been repaired. Open Xinzhi software, and find the annotation diagram, dot bitmap and schematic diagram of iPhone XS Max.

IPhone XS Max mobile phone screen does not display fault maintenance figure 1.

IPhone XS Max mobile phone screen does not display fault maintenance figure 2.

IPhone XS Max mobile phone screen does not display fault maintenance figure 3.

Find the connector of the display screen and measure the resistance of each pin of the connector. It is found that the resistance value of PMU_TO_DISPLAY_RESET_CONN_L line at pin 5 of the socket is unstable, and it is determined that the wiring of the circuit board layer has been broken.