Logitech X-540 repair Help

[boulepick]

Hello to all,

i need help repairing my logitech x-540 i have made the mistake of plugging it to a high current of my a power surge protector and ever since no sound is coming out. it turn's on i see the green light that it is on but no sound is coming out, not even a crack. i check the fuse for continuity and it is good. what might be the problem? can anyone point to the right direction of repairing it?

thank you

i have uploaded a front and back end of the board,

 

[CocaCola]

i have made the mistake of plugging it to a high current of my a power surge protector

Can you elaborate?

 

[boulepick]

Edit : i have an APC C5 10 Outlet Power Filter for protection against power surges, pikes and lightning. it has 2 High Current Filter outlets. i plugged the logitech in one of them and since them no sound is coming out of the logitech. it will turn on but no sound will come out of any of the speakers. what must i check or replace to get it back working again. don't know what more information you require.

 

[CocaCola]

I'm just confused about what these 'high current filter outputs' are and why you suspect they damaged it... The device will only draw what it needs, doesn't matter if you hook it up to a plug that supply 15 or 20 amps it's only going to draw what it needs... It's the voltage input levels that are important here, if you mixed them up there could very well be issues...

Have you tried a different input source to see if that changes anything? Also push and twist the volume knob a bit while something should be playing and see if you can get any reaction, might be something faulting in the remote... Does the headphone jack on the remote work?

 

[boulepick]

ok well it may not be the cause of why it stopped but it maybe just a coincidence it stopped working after plugging it in the high current filter. i have tried pushing and twisting the volume knob with no reaction. the headphone remote work, when i plug a headphone in the remote i get sound when the unit has power or not.

 

[CocaCola]

Well the headphone test proved that we at least have a valid input signal... Now we likely know that the amplifier circuit is at fault...

So now you need to identify the amplifier chips (the two upright chips) and pull datasheets and see what voltage certain pins are supposed to be at and verify they ware working or at least have power...

Also hands on is always better, look closely at the entire board, do you see any burn marks or any obvious signs of damage to any part?

 

[boulepick]

i checked and no burn marks on the board, you can see on the attachments that i added to this thread. i'm also attaching the datasheet that i have found for the amplifier chip but i don't know much on how to check for the voltage. i have a tester and pretty much technical but i would need your help on how to test for it. i'm adding the wattage specs on the owners manuals.

Total RMS power : 70 watts RMS
Satellites : 45 watts RMS(2 x 7.4w front, 15.4w cnter, 2 x 7.4w rear)
subwoofer: 25 watts RMS
Total Peak power : 140 watts