Samsung 51" Plasma PS51D450A2M

[tom66]

Re: Samsung 51" Plasma PS51D450A2M

Post a pic of the control board, let's do a test before you order anything else.

[gadget78]

Re: Samsung 51" Plasma PS51D450A2M

ok cool, will get a pic up tomorrows evening, as not with TV till then (only the PSU!) ...

Thanks you

[gadget78]

Re: Samsung 51" Plasma PS51D450A2M

ok after having another play...
found your post here
https://www.badcaps.net/forum/showth...ht=lj41-09475a

got same control board, with the jumpers on it, where you said jumpering pin 4-3
gets you test mode, so have tried that, with all connectors on, and just jumper, still exactly the same
(tried with mainboard ribbon disconnected too, still same)

if i manually tie VS_ON high like before on bench, but not with it connected up should i see something ? or is it not advisable ??

EDIT
ok so i did that, tied it high, and Vs starts rising gets to a couple volts, where you can also hear quiet clicks, and stops, voltage to zero, relay kicks out, couple seconds and it starts doing it over again ..
now when powering up initially, can actually hear this as well 2-3 clicks and small amount of voltage..
so it must be trying to switch on..

also my mistake, that green light, counting seconds when its on/off is actually
on for 6 seconds, off for 2 seconds, back on 6 seconds etc etc ...

cheers.. Mick ..

[tom66]

Re: Samsung 51" Plasma PS51D450A2M

6-2 indicates a fault. Are all ribbon cables and power cables to the sustain and control boards connected?

[gadget78]

Re: Samsung 51" Plasma PS51D450A2M

yeah 6-2 when all cables are connected ...
(have tried reseating all cables too ... did that first as tv was working fine before putting into storage in garage... have also double checked for small chip/cracks on screen again today !)
but yeah its pretty much 6-2 whenever !!

[gadget78]

Re: Samsung 51" Plasma PS51D450A2M

had some more time to put into this TV today ...
removed the YBuffer and XBufer main boards..

an have found that the Ybuffer board LJ92-01760A (the larger of the two boards on left)
has Short between GND and SVC_Yout, and SVC_VS
so yeah thats a problem ! ... now going to start removing items untill i isolate the short...
will update post once i find it etc ! Could be anything cap, a fet (are they) or a diode i suppose .. will start with the bigger things first!

[tom66]

Re: Samsung 51" Plasma PS51D450A2M

If the Y-buffer has a short between those terminals (very rare to short to GND directly) then I would suspect the buffer ICs...are you sure you mean the buffer board not the Y-main??

[gadget78]

Re: Samsung 51" Plasma PS51D450A2M

yes prob do mean Y-Main...
confirmed thats its got a few bad chips
diode SF10a400 dead short, also couple of RJP30H1 ...
X-main, an x-buffer seem ok, as does the actual y-buffer (know i know what they called !!)

have ordered a Y-main from ebay, as by time i get a few components, still not 100% on rest of smaller components on board etc !! plus found one for 12.95 on eBay so worth a shot !!
will keep ya posted...

[gadget78]

Re: Samsung 51" Plasma PS51D450A2M

just a follow up, with new y-main board on, all working

logic board flashing every second (evenly, sorry didnt pay attention properly at first )
the jumper on 3-4 (or any of the others) doesnt induce a test mode oddly ??

but TV is working fine so im happy
cheers Mick ..

[tom66]

Re: Samsung 51" Plasma PS51D450A2M

just a follow up, with new y-main board on, all working

logic board flashing every second (evenly, sorry didnt pay attention properly at first )
the jumper on 3-4 (or any of the others) doesnt induce a test mode oddly ??

but TV is working fine so im happy
cheers Mick ..

For future reference, the LVDS cable must be disconnected from the control board for the 3-4 jumper to initate test patterns. And it must be disconnected before it is powered up.

[gadget78]

Re: Samsung 51" Plasma PS51D450A2M

arrr yes that would explain it ! .. many thanks once again...