LE40M87BD restarting

[sordids999]

hello

tv keeps restarting itself voltages seem ok read it could be cold solder joints tried that tv worked all evening,but now this morning testing it again and the tv has restarted and is stuck in a loop of doing this

just wondering if anyone has come across this fault ?

thanks

[tom66]

Re: LE40M87BD restarting

On these it's usually the main board at fault. cold solder under processor (BGA) or bad cap near processor.

[sordids999]

Re: LE40M87BD restarting

ok thanks ill check now

[sordids999]

Re: LE40M87BD restarting

tom do you mean under the metal heatsink with the caps etc ?

[tom66]

Re: LE40M87BD restarting

Yeah. The shield is soldered down; Not done one myself though, so can't be sure on the exact parts that fail.

[Alastair E]

Re: LE40M87BD restarting

Aye--Could be the two 1000uF 10V caps under the tinwork cover by the processor.

There's a row of 100uF SM Caps by the power-socket near tinwork that can cause issues too...
--When done--you must replace tinwork--or the processor overheats--there's dead-toad pad from two chips to the tinwork.....

[sordids999]

Re: LE40M87BD restarting

thanks alastair i have highlighted the caps do you mean those two and can you point me to the 100uf caps please

thanks

[Alastair E]

Re: LE40M87BD restarting

Yup--Those are the 1000uF caps...

The 100uF ones are the three between the socket and the tinwork, (There's one pink-top poly cap-thats usually OK in the row) plus the couple that run at right-angles to that row and along the bottom of the tinwork--All can be suspect....

Bung a 'Scope on them--You'll see horrible switching noise/ripple on 'em....

[sordids999]

Re: LE40M87BD restarting

UPDATE:
Changed the 1000uf caps on the main board still restarting also went into service menu set ready to on and been working now for two days

Thanks to Tom for the pointer on the READY option

[newtothis]

Re: LE40M87BD restarting

Nice one

[budm]

Re: LE40M87BD restarting

What the heck is the 'SET' function for. I am glad you and Tom figured it out.

[tom66]

Re: LE40M87BD restarting

The READY option appears to be some kind of watch-dog. If it is turned off, the set will reboot approx every 10 minutes. READY might get turned off by corruption to EEPROM. Very odd fault.

[budm]

Re: LE40M87BD restarting

Thanks.

[noledud]

Re: LE40M87BD restarting

hi all iv just tried this and it kills the free view can anyone confirm this ?

[noledud]

Re: LE40M87BD restarting

the ready option i mean not the caps not tried that on this board but had n o luck with that in the past on the same board

[tom66]

Re: LE40M87BD restarting

Didn't kill the Freeview on other sets I've tried it with.

[noledud]

Re: LE40M87BD restarting

mines strange it would go off if ready set to ON

Iv set mine to off and it no longer restarts but when its off the digital tv is "unavailable"

strange but working thanks for the tip !

[geofpt]

Re: LE40M87BD restarting

It's 5 years after the last post, but I had the same problem of restarting. After hours of searching and pondering changing caps that did not look damaged, I came across the READY ON solution and it works. If Tom666 is still out there "THX". Well played and figured out. At least I now have schematics which I could not find anywhere else.