Skip to main content

The Sonos isn't working, but the LED flashes white every 10 seconds. It doesn't seem to fully boot up, and after 10 seconds it reboots.

As ukpicasso and Timc995 when injet voltage then power ON  

 

 

After testing, I can measure 14.5v to 13.10volts at the injection points and the same voltage at the green points, with no more power than this board, that is, with the ribbon cable disconnected.

 

When connecting the second board with the ribbon cable, power consumption increases and the voltage drops to 5V - 0V, so the device restarts, entering the cycle I explained at the beginning.

 

With the 24V injection, everything works at 100%.

Does anyone know what could be wrong with keeping the voltage stable when the device is consuming power?

There are 330V at the blue points.

Does anyone have a possible solution, or is someone experiencing the same problem?

 

Thank´s 

My issue isn’t exactly as you have described but below may provide some clues

My Play 5 Gen 2 dropped from about waist height and stopped working completely. After checking all the usual suspects (fuse, FET etc), all are working ok so no issues with the input AC power circuitry.

I had same issue as some others whereby there was no DC voltage on the low side of the DC-DC transformer. I had 330VDC on the high side and nothing on the low side. I removed the CMOS FET (Toshiba TPW1500CNH) that is between the 3 caps and transformer as suggested by timc995. The FET was shorted, i.e., the diode voltage between Source and Drain was 0, whereas it should be ~ 0.5-0.7V

 

Injecting 24V using a standard AC to DC converter (24V 5A) to the injection points in the image above works perfectly and SONOS Play5 Gen 2 is back to life. I did not try injection of 24V with the MOSFET present so not sure if 24V injection works with the MOSFET there. With the my blown MOSFET there, the injection points (board unpowered) are shorted. With the MOSFET removed, they were open, as expected.

My suspicion is that the physical drop caused shock or vibration and damaged the transformer windings or internal structure leading to a failed transformer and then powering it on with a damaged transformer led to high current through the MOSFET damaging it and shorting the source to drain. I don’t have the time nor patience to replace and debug the transformer so am happy with the 24V injection solution.

I piggy backed on the AC power connecter by removing the Fuse and Cap connected to the white power connector shown below, soldering wires from the free via holes left from removing fuse and cap to the 2 injection points for 24V. The DC output of the AC-DC adapter can then be connected directly to the power connector of the speaker.

  1.