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Solution: Redmi Speaker and Handset No Sound

The loudspeaker does not play the music when turn music on, and there is no sound on the phone when it is called. How should we fix it? Let's test and repair in this article!


First check whether ReMMI is in the headset mode. After checking, Redmi has no headphone mode, but speakers and mobile phones are still not working.

Disassemble the Xiaomi Redmi by phone opening tools, use digital multimeter to measure the EAR_DET voltage, after measurement, there is no voltage and it is short circuit， R1904 is short circuit.

Using precision titanium alloy tweezers to remove R194, it is found that capacitor DCDHSSHDEET is short circuited.


Check Redmi schematic diagram, we know that CDC_HS_DET leads to a Redmi power supply IC. Test the Redmi, we find the power supply IC is overheat, replace the new Redmi power supply IC.

Now find a 2.2K (222 capacitor), and then replace the R1904 capacitor, use QUICK 861DW hot air rework station to solder it with jump wire.


Welding ReMMI power IC, and then open the ReMI test, the headphone detection voltage 1.8V is normal, disconnect the power, and then install Redmi, after testing, the headphone loudspeaker and cell phone work, repair end!

If you want to get more technical support about cell phone repair, please contact us on www.vipfixphone.com

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