Sony DAV-S880 (HCD-S880) home cinema Standby red LED blinking

[Chungalin]

This Sony home cinema doesn't want to turn on. It keeps blinking the red standby LED when trying to turn it on.

I've given a chance to ESR meter on power supply and only C914 (47uF/35V) and C901 (4.7uF/50V) show abnormaly high ESR (larger than 50Ω). The first one is the Vcc filter cap for primary switching regulator IC (SanKen STR-F6267), so looks promising. These caps are close to IC heatsink, they suffer a lot.

I change both and done!

After searching (adding C914 to search terms) I found that other Sony home cinemas sharing this PSU (or PSU design) will fail the same way: DAV-S550 (HCD-S550), DAV-C770 (HCD-C770), DAV-C990 (HCD-C990). Maybe others.

[ReeceyBurger123]

Re: Sony DAV-S880 (HCD-S880) home cinema Standby red LED blinking

Nice one, what brand and series are the caps ?

[Chungalin]

Re: Sony DAV-S880 (HCD-S880) home cinema Standby red LED blinking

These were small and only manufacturer logo was visible, the circle with 3 flaps: SAMYOUNG.

[Chungalin]

Re: Sony DAV-S880 (HCD-S880) home cinema Standby red LED blinking

This one has come back to the workshop with a new problem: it's behaving like FUNCTION button is constantly pressed.

First thing that comes to mind is: bad tactswitches. But not so fast. Although they show some aging (not perfect short, some ohms remain when pressed), the set does the same if I disconnect the front PCB with all tactswitches.

After some disassembly, I see that under DDCON PCB, a weird oxidation has developed under CN804 connector (from keyboard). I clean it with Sidol metal cleaner and it's fixed.

Then I notice that DVD mechanism fails on detecting Limit, it keeps pushing optical pickup towards the Spindle motor for one second before giving up (and not reading disc). These ones carry an expensive and hard to find Mitsumi TDP022W mechanism (relabeled by Sony as DBU-1) that implement limit sensing with a switch mounted on the pickup that touches a plate when reaching limit. Luckily, this switch can be taken apart from pickup and disassembled, then softly brushed inner contacts with some metal tiny tool and then reassembled. After this, no more problems.

The odd thing is that customer insinuated that this failure should be repaired under warranty from the first PSU failure (december 2015). Most of the times, customers are the worst "failure" I have to face. Of course I rejected this idea, and said that this is a new failure completely unrelated to first one!! Does this happen to you too?

[MrJoy]

Re: Sony DAV-S880 (HCD-S880) home cinema Standby red LED blinking

I have two SONY DAV-S880's, and both have had the same power supply problem, where the standby red LED blinks indefinitely.

The power supply in the Sony DAV-S880 is shared by several other models, including the DAV-C770.

I read a blog post about repairing the C770 power supply for the same issue (google dav-c770repair, first link that comes up), which points out the C914 capacitor as the common fault. (https://sites.google.com/site/hancoc...dav-c770repair)

I decided to try it out, and bought a couple of "RND 150ENR470M35B - Aluminium Electrolytic Capacitor Radial 47 uF 35 VDC" capacitors.

The power supply itself is easily removed, but you need to take care with the current stored in the large capacitors even when removed for a while. Use a 60W light bulb or larger, and a lamp or socket that you can hook up to a wire, and connect the leads to the capacitor solders on the backside to discharge the current. For me the large C912 450V cap really made a flash, so be extra careful to short ALL capacitors.

Google "service manual" and "DAV-S880" or other models to get the manual with excellent schematics and PCB drawings.
()

The PSU board itself is also very well marked with all capacitor names (except the C914 cap which is not marked for some reason. Use the drawing to find it).
After removing the C914 cap with a normal solder iron, I checked it with a multimeter for resistance and keeping charge. Both seemed to behave normally, but when measuring with an LCR meter, the capacitance value showed 1 where it measured 0.05 on the replacement caps.

I soldered in the new capacitor, and now the first DAV-S880 works as normal. I'll do the same repair on system nr. 2 soon, and will post an update on that one as well.

[Maxamillion]

Re: Sony DAV-S880 (HCD-S880) home cinema Standby red LED blinking

This Sony home cinema doesn't want to turn on. It keeps blinking the red standby LED when trying to turn it on.

I've given a chance to ESR meter on power supply and only C914 (47uF/35V) and C901 (4.7uF/50V) show abnormaly high ESR (larger than 50Ω). The first one is the Vcc filter cap for primary switching regulator IC (SanKen STR-F6267), so looks promising. These caps are close to IC heatsink, they suffer a lot.

I change both and done!

After searching (adding C914 to search terms) I found that other Sony home cinemas sharing this PSU (or PSU design) will fail the same way: DAV-S550 (HCD-S550), DAV-C770 (HCD-C770), DAV-C990 (HCD-C990). Maybe others.

Thanks for the infoe. Have just replaced C914 and my Sony Dav S880 is up and running again. I am a retired field service tech and had diagnosed the fault to the PSU.