Author Topic: Sony DVP-S725D Won't read DVDs but will read CDs  (Read 2307 times)

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Offline paul_g_787Topic starter

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Sony DVP-S725D Won't read DVDs but will read CDs
« on: September 12, 2020, 05:31:26 pm »
Hi everyone. I am having problems with my DVD player and am hoping someone might know a bit about this kind of issue.

I have a Sony DVP-S725D DVD/CD Player I purchased new when it first came out, a very long time ago. It was approximately £500 at the time.

About 15 years ago it stopped playing DVDs, So I shelved it. I recently found the player in the loft while having a clear out, so I though I would have a look to see if I can repair it.

I powered it up and it works great playing CDs, however it will still not reliably play DVDs. Sometimes it will after loading a disc 4 or 5 times but it will usually come up with ‘No Disc’ or error C13 (disc is dirty according to the manual).

Of course I tried cleaning the discs a few times, however no joy, but they all play in my other DVD player fine.

I have a lens cleaning CD with a little brush on it, which I tried. No luck.

So I took the top cover off and the player is still immaculately clean inside. I was expecting it to be dusty. I had a look at the laser lens and it is perfectly clean.

I cleaned the laser lens using a CD player lens cleaner (think it is just Isopropyl alcohol), and a cotton bud. However this has not helped. I tried again and the player will play CDs fine but still not DVDs.

So I have had a research online and have found that this is a common fault with this model. I found four different forum threads that ended in the poster replacing the lens assembly.

I would very much like to get this player working as it is the best picture I have ever seen on a DVD player. The modern ones are just not as good.

Does anyone have any advice or suggestions on this?


This is the service manual:
https://www.manualslib.com/manual/1054052/Sony-Dvp-S725d.html

Attached is the user manual.
« Last Edit: September 12, 2020, 07:25:55 pm by paul_g_787 »
 

Offline Haenk

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Re: Sony DVP-S725D Won't read DVDs but will read CDs
« Reply #1 on: September 13, 2020, 07:57:30 am »
Replace the laser pickup.
The pickup is actually "2-in-1", i.e. there is a CD- and a DVD-part. If one of the two fail, the whole pickup needs to be replaced.

Unfortunately, the replacement pickup (even on Aliexpress) is quite expensive. (40-50 USD, but look around, maybe it's cheaper somewhere)
 

Offline paul_g_787Topic starter

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Re: Sony DVP-S725D Won't read DVDs but will read CDs
« Reply #2 on: September 13, 2020, 07:08:32 pm »
Replace the laser pickup.
The pickup is actually "2-in-1", i.e. there is a CD- and a DVD-part. If one of the two fail, the whole pickup needs to be replaced.

Unfortunately, the replacement pickup (even on Aliexpress) is quite expensive. (40-50 USD, but look around, maybe it's cheaper somewhere)

I dismantled the drive today and the pickup is (as stated in the service manual) a KHM-220AAA.

I see what you mean about the laser being a 2-in-1. I have watched a whole bunch of YouTube videos and most of the pickups out there have two separate lasers with two adjustment potentiometers. I can see that this one only has one potentiometer, so as you correctly pointed out, this indicates the 2-in-1 laser and because of this I cannot adjust the DVD pickup separately.

That being said, I tried to adjust the potentiometer anyway (you never know).

To recap, the player plays CDs fine but not DVDs apart from sometimes.

The initial value was 1.461KΩ I adjusted it as follows:
1.098KΩ -  Made no difference
0.791KΩ -  Made no difference
0.341KΩ -  Made no difference

So I decided to adjust it the other way:
1.996KΩ - Sort of read a DVD. Would load the initial language select screen but when trying to load the menu it would not track and then say error C13
2.38KΩ - Same as the last reading
2.63KΩ - A little better this time. Picked up the disc straight away. The DVD loads the menu but will not play any videos (main feature or extras).
3.12KΩ - This would not work at all. Could not detect DVDs or CDs at all.
4.64KΩ - Same as above.

So I have adjusted it back to 1.465KΩ (as close as I could get back to original. And now the problem is back to CDs working but not DVDs.

I tested 4 different DVDs (2 Single Layer and 2 Dual and also 2 different CDs with every one of the above readings.

So This is probably the pickup like you said as far as I can tell.

I have emailed Sony to see if they sell the pickup still. They will probably charge a fortune though. The cheapest I can find one is £28 on Ali Express UK.
 

Offline Haenk

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Re: Sony DVP-S725D Won't read DVDs but will read CDs
« Reply #3 on: September 14, 2020, 06:55:45 am »
I didn't have any negative experiences with pickups from china yet, though the packaging is always bad. Sony probably charges more than a used, working player.
 

Offline ambrosia heart

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Re: Sony DVP-S725D Won't read DVDs but will read CDs
« Reply #4 on: September 14, 2020, 01:14:15 pm »
Use an oscilloscope to measure the RF waveform helping you to decide if an optical pickup has been ageing.
By adjusting the VR of the optical pickup, the amplitude  of the waveform will be adjusted and matched with the waveforrm stated in the service  manual. If the RF waveform of DVD is unclear with amplitude low, this means the DVD laser diode is dead. :popcorn:
Buy at taobao is another option.  You must however ask the seller if this optical pickup is new.




 

Offline cheeseit

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Re: Sony DVP-S725D Won't read DVDs but will read CDs
« Reply #5 on: September 14, 2020, 05:56:33 pm »
You can buy several working used units for the price of one 'new' optical pickup. The same model pickup is used in many other units.

If you manage to adjust the laser power to get it working - assuming that's the pot you're twiddling - then enjoy whatever usage you may squeeze out of it because it will kill it in a short while.
 
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