PHILIPS 30PF9975/12

[chrissie jones]

got this old lcd tv in today..when switch on,gose orange then flashing red light only..got anything on this set lads...thanx chris...

[jpower]

Goodmorning from GREECE,replace all the capacitors near ic mc34068 on the aux suply,its the small pcb

[nicam49]

Hello All! Ok, it's an old thread, and an old TV, but here's some info that might help or at least be of note. The above symptom I also have, but if I warm the right-hand-side of the aux power supply with a hair dryer, and then switch the set on, it works!
So far I've tried narrowing down the problem area by zoning the heat, but no definitive result yet. work is ongoing. I have already changed the 2 mosfets 'just in case' .
Hoping it's not an smd on the underside of the board as my soldering skills are not that great.
 

[jordan]

Check R-3031 and R-3032 (all 150KR)

[nicam49]

Hi! thanks for your reply, much appreciated. Those resistors are fine, but I'm guessing they're the usual suspects?
This is an interesting problem....if I warm up the area around C2014 and C2011, then it works fine. Even after I've taken the heat away it carries on working. Need to get some more capacitors, so to be continued. (I hope)

[downunder]

The Philips bulletin might be more appropriate where the tv goes into protection from a cold start.

The bulletin states:
Remove R3031 & R3032 (150K each) from the board and replace with a 27K-5W fitted at position 3028.
Replace C2002 (330u-25V) and C2003 (680u-25V).

Bruce

[vlado66]

Replace T7005 and T7006 on AUX PSU board

[nicam49]

Hi Vlad, thanks for you help ! :-) I had changed those fets already, thanks-tho' much appreciated.

Hi Downunder, thanks for your time and input and for sharing your Philips bulletin knowledge,....now I'm going to get onto those changes as soon as I source the parts tomorrow...you've given me new hope....good on ya! 
Best wishes to Both,
Nick

[nicam49]

In case anyone else is following this thread, the result of following downunder's advice from the Philips service bulletin, is....a result!  I had been troubleshooting a cold start issue; the set worked fine if I warmed up a section of the aux supply board, but couldn't find anything wrong in the warmed-up area. Changing those 2 resistors and caps - not because they were faulty, but for different values- has resulted in a fully working set. None of the parts were faulty! It was a circuit mod issued by Philips. I could have changed parts forever and still not fixed the set.
I would like to know HOW  we get access to the Philips service bulletins; if it hadn't been for downunder's knowledge and willingness to share it on the forum, this set would now be in landfill...I wonder how many more were scrapped because Philips service bulletins aren't accessible, even for old models ....once again....thanks BRUCE !

[downunder]

Hi nicam,

I'm pleased that worked for you, and thanks for the feedback.

Service bulletins, whether it be Philips or any other maker, are only available to their authorised service agents. If you're not an agent, they usually give you short shrift when you make an enquiry of them.

I don't have any agencies, but over the years I've gleaned little tidbits from various sources, and had the foresight to store them for a rainy day. The brain box can store and recall only so much and then oldtimers sets in. Euras Service Data would be a good source for service tips, but for struggling techs who have to feed their starving wife and kids, it's probably not affordable.

Once again, well done and bravo.                          Bruce

[nicam49]

Yes there is a service bulletin on this fault. Pm me for details