Philips PHP-X19 2 seconds to black problems

[roobarbthedog]

Re: Philips PHP-X19 2 seconds to black problems

Sabre - thanks for the suggestion. The board on the reverse of these components looks slightly scorched. I'm hoping it is not the lamps as this makes the job expensive and probably not cost effictive. I'll try the lamp test later and see if I can rule them out.

[sabre504]

Re: Philips PHP-X19 2 seconds to black problems

This is a very common problem with this monitor

All these things seem to go at the same time ,lamps,caps and the 2 drivers i have marked in the picture MTD3055VLT4 N-Channel Power MOSFET 60V/12A, DPAK if i remember the number correctly .

If you replace all the caps apart from the large one and the lamps and you are still getting 2 secs to black you may have to change the 2 mosfets.

[PlainBill]

Re: Philips PHP-X19 2 seconds to black problems

What I would do at this point is connect the signal card, IPS (inverter / power supply), and CCFLs together and hook up AC power observe if one CCFL is the source of the pink glow.

PlainBill

[roobarbthedog]

Re: Philips PHP-X19 2 seconds to black problems

Costs so far are about 4GBP for parts (probably cost more in petrol driving to Maplin and RS!!!).

[roobarbthedog]

Philips PHP-X19 monitor Problems.

Ok, here goes. I've got a Philips PHP-X19 monitor that my son uses for his PC. We've had it for at least 5 years, and it does get used a lot and I'm forever telling him to switch the PC off when not in use (incidentally, the power supply on the PC fried last year and had to be replaced).

Anyway, a couple of weeks ago the monitor started experiencing the “2 seconds to Black” problems. I've been doing some internet searches and I've found some useful articles on this forum. Coincidentally my Technika 22” TV/DVD had also gone kaput a couple of weeks before and I got this working by replacing 2 bad caps on the power board (I'll post this on another thread).

Feeling confident, I decided to have a go at fixing the Philips monitor. After wrestling the back cover off (and this was not easy. Lots of plastic clips to prise open), I managed to get access to the power board. 2 caps were slightly bulging (470uF 25V Xunda caps) and I replaced these with the same rating caps bought from Maplin (unbranded – should have gone for Panasonics that I can get from RS Components, but Maplins was closer). The rest of the caps visually seemed ok. I plugged the various connectors back in (left the screws off for now) and managed to get a stable image on the monitor for about 20 minutes, then it resorted back to the same problem. I then replaced the other 4 big caps with the same rating Panasonic FM caps (680uF, 25V Xunda caps) but still got the same issues. My soldering was a bit ropey on the initial repair so I re-soldered the 2x470uF caps. Still getting the “2 seconds to black”.

When I did get an image on the monitor it was tinged red/pink, and I've seen elsewhere that this could be an issue with the CCFLs. I could also see the faint image in the background, without shining a torch. So I stripped the monitor down further and managed to get access to the tubes. As you can see from the attached images these are black at the ends and are probably knackered. Both sets of CCFLs are black at the ends.

Before I go and order replacements, is there anything else I should be checking? Is it worth recapping the rest of the power/invertor board? There is a bit of scorching on the board near 2 transformers, but I can't see any damage on the reverse side of the board. I've got an ok multimeter so can check some basics. The monitor is in pieces at the moment and I can get some more pictures. We don't get much sunshine or daylight this time of year in Scotland, or any other time of the year for that matter, so getting decent pics is tricky.

Caps replaced – C216, C215 (470uF 25V), C214, C213, C212, C211 (680uF 25V).