20 Most Recent Fujitsu Plasmavision P42HHA10 42 in. Television Questions & Answers

I have recently fixed my P42HHA10AS 42" plasma which had problem of random picture shutdown.
Would run ok for periods, (sometimes 30 mins, sometimes 2+ hours), picture perfect.
Then it would randomly fail - with loss of picture and front panel led indicator goes from green (normal) to flashing red continuous.
After switch off, removal and re-application of power it would often re-start and run normally for a while.
Sometimes it needed to be allowed overnight to cool before it would run again.
I also noticed that the failures generally coincided with any change to the screen display mode or input mode settings, sometimes just the connection of an external cable for DVD player etc would cause a failure.

Fujitsu service supplied service manual and Service Bulletins regarding this problem :-
Service Manual P42HHA10 is available at http://www.eserviceinfo.com/download.php?fileid=41950

Service Bulletin PDP 0040-01 Main Digital pcb see http://www.eserviceinfo.com/download.php?fileid=43455

Service Bulletin PDP 0068-01 Main Digital pcb see http://www.eserviceinfo.com/download.php?fileid=43450
Service Bulletin PDP 0035-06 Main Power pcb see http://www.eserviceinfo.com/download.php?fileid=43471

Worked through the service manual checks (service manual very basic- overview / DC voltages only - assumes availability of replacement modules). The troubleshooting flow charts lead you nowhere helpful.
Could find no fault with the main power board, except that the 6.5V(nominal) was actually 7.4V at CN351 Pin12.
Added 2x Schottky diodes (1Watt) in series with the transformer 6.5V output winding - this lowered the output voltage to 6.6V. - However, this made no difference to the continuing fault condition and is likely not related to the fault condition.

This units problem was fixed on implementation of Service Bulletin PDP 0068-01 Main Digital pcb.
No other faulty components were found.

The mounting solder on the main processor socket was cracked on one corner at the pcb mount point. (See last picture in PDP 0068-01, page 2)
Re-soldered all processor socket mount fillets, and the set has worked faultlessly since.
Extreme care must be taken with this process, as excess solder will melt / distort the socket.
I became convinced over time that the fault was to do with the main processor board, as the failures were so random, and the set would otherwise run perfectly.
This fault is caused by a combination of solder fatigue, vibration and the thermal cycling of the pcb over time.
I expect it is a common cause of many of the reported problems experienced on these Fujitsu panels.
I suggest that the above work should only be attempted by suitably skilled person/s, as very fine soldering and knowledge of electronic pcb repair techniques are required.
Johnb1111.