Samsung Galaxy S5 no sound

[califauna]

Hi, I'm new here.

I have an S5 which produces no sound through either the top or bottom loudspeaker. The top loudspeaker produces a constant, very faint high pitched squeal.

I have tried:
1. Using the housing of another S5, as this housing contains the top loudspeaker.
2. Replacing the bottom loudspeaker with a new one.

The symptoms do not change after the above changes. The phone works fine apart from this.

I have a soldering station, multimeter, hot air gun, handtools, etc.

Thanks for any troubleshooting and repair help.

 

[califauna]

I've found that actually the ear speaker (not main speaker) is working. Turning up the 'in call volume' in setting I can hear it over the squealing sound. No such luck with the ringer volume, or playing music/Youtube videos though, which produce no sound at all through the main speaker.

 

[davenn]

Hi, Welcome

I've found that actually the ear speaker (not main speaker) is working.

that was going to be my Q ... so we now know that the main audio circuit is OK
it may be the small amplifier(s) circuit(s) that power the speakers that is the problem

 

[califauna]

Sound also works out of the headphones connector.

 

[califauna]

For others with the same problem, I have found out that my MB was completely missing a 'Low frequency filter' component. It must have fallen off at some point.

EDIT: According to the service manual this component is an 'inductor', and from what I gather is the same component as the one next to it. Seems to be possible to buy this component online if you search for the part number (2703-004597).
https://mega.nz/67a9bdf9-8fff-449f-95a6-f5937fdda781

I guess if you have two S5s you could transplant one to the other (to the detriment of your other S5 of course).

If it is a filter I'm not sure why it would be a low pass filter (inductors behave as low pass filters don't they) rather than a high pass filter, but at any rate this guy seems to have bridged the contacts and his speaker works:

 

[Harald Kapp]

not sure why it would be a low pass filter (inductors behave as low pass filters don't they) rather than a high pass filter

1. Inductors can be used in high pass filters, too, depending on where in the filter circuit you insert them.
2. But I agree it is most likely a low pass filter. For one to suppress high frequency noise (omnipresent in fast digital circuits such as a cellphone).
   Secondly the cellphone may use a class-D amplifier for efficiency. In this case the digitally amplified signal needs to be low-pass filtered to remove the artifacts from the switching amplifier.

It will be interesting to hear if you manage to perform the repair.

 

[califauna]

Soldered across the contacts where the smt inductor was. Speaker now works but has more noticeable distortion than before. Will suffice though, as I'll be using the jack output when I need high quality audio anyway.

The problem appears to be caused by the proximity of the component to one of the ribbon connectors on the board. Repeatedly disconnecting and connecting the cable increases likelihood or knocking the component. I've seen a couple of other posts videos online with the same problem so I doubt it's just a coincidence that particular component fell off with them as well.

 

[Harald Kapp]

Speaker now works but has more noticeable distortion than before.

To be expected as the low pass filter is missing.