Way to Fix Process for iPhone 6 Speaker No Sound

Fault Description: iPhone 6 Speaker No Sound.

Possibility Fault Sources: Software Error or Sound IC Driver Error

Solve way: We will disassemble it and test the voltage, according to the value to decide the next step.

Following the repair process:

First check to see if iPhone 6 speaker has no sound when receiving calls or playing music. After checking, there's really no sound coming out of the IPhone 6 speakers, it just keeps silence. However, when we insert earpiece, sound can be heard normally. This means the iPhone audio IC is normal, so the fault may be in the speaker or audio power amplifier circuit.

Disassemble the iPhone and then use multimeter to measure the resistance value of 1# and 2# on charging port flex cable connector, the data is normal, which means the loudspeaker buzzer is normal. Keep going to measure the resistance between 1# of J1817 and grounding, 2# and grounding, the data is normal, this means that there is no problem with the circuit from the charging port connector to U1601.

Take off the iPhone motherboard and observe it under the 7-45X Trinocular Stereo Microscope, there is no water damaged or moldy conditions. Put iPhone motherboard on PCB holder fixture. Blow shield cover with hot air gun and remove it with curved tweezers.



Now connect iPhone motherboard to DC power supply to measure the power supply voltage of U1601. Measure the voltage of the corresponding capacitor C1635, the data is normal. Continue to measure the filter capacitors C1603 around U1601, the problem was found, the voltage value is 0, it's abnormal.

Measure the diode data between C1603 and grounding with Fluke 15B+ Digital Multimeter, the data is normal. Since C1603 is output by U1601, so we suspect the fault is U1601. Remove the U1601, clean tins and then apply some low-temperature tins to the solder pad, and then measure the resistance between A6# of U1601 and grounding, now it's normal.

Measure the resistance between A2# and grounding, the data is 0L, it is open circuit. Because U1601 A2# and B2# are connected to the battery cathode through L1604, so now we suspect the fault is L1604.

Replace the new L1604, and then measure the resistance between A2# and grounding again, it's normal now. Now, solder the U1601 with QUICK 861DW again, after finish that, assemble the iPhone.

After we finished the above step, we test it and boot it again, the music can be heard and the call also can runs normally.So we think this is a succeed fix, of course ,if you have any good idea, welcome to add my Whatspp to discuss it.