Redmi K40 is not turned on (battery is out of power and tail plug cable is damaged)

Redmi K40 is not turned on (battery is out of power and tail plug cable is damaged).

What causes a Redmi k40 not to turn on? Let’s see how to repair it!

[Fault model] Redmi K40

[Fault phenomenon] No boot.

[Maintenance process] I received a machine sent by a customer for repair, the model is Redmi K40, and the fault is that it does not start.

Redmi K40 does not boot Figure 1

Remove the motherboard and power on the single board to see the current. It is found that the current jumps at 300mA, which is normal. It can be turned on according to the current. After measuring the battery voltage, it is found that the battery has no voltage at all. It seems that it is starved to death. Use an ammeter to activate the battery, and there will be voltage. Charge the battery voltage above 3.6V, and the motherboard can be turned on. There is no response when the charger is plugged in. After removing the charging cable, it is found that the inline seat of the charging cable is buckled.

Redmi K40 does not boot Figure 2

Replace the new cable and you can charge it.

Redmi K40 does not boot Figure 3

[Maintenance Result] Install the motherboard into the shell.mobile phone

It can be turned on normally, and the functions of WiFi, Bluetooth, voice, charging, fingerprint, taking photos and making phone calls are all normal, so the maintenance is over.