Beovision 7-40 problem : trying to repair

5 replies
E(
Eskobar (archived2)
Bronze
14 posts
Posted October 26, 2020 at 12:42 GMT
#2145982

Hello,

My Beovision 7-40 mkII have problem :

- no screen/sound

- active standby diode is okay

- if I active "TV" button with beolink (press a lot of times insisting), led screen post "TV" 2 seconds

- if I open DVD, reading time is different if I take DVD or Bluray (not understand Bluray)... I guess it makes the difference in reading between the 2 DVD / BD formats.

- CPU rom is okay (voltage value is okay)

The B&O shop says "there are no more parts"...

All PCB are good, but main chassis PCB 999 have defaut (with help founded : link)...

I opened TV with a friend who knows about electronics. We observed :
- thyristors have instables values > I have changed full thyristors
- Now thyristors values are okay
- 2 inverters of 3 are not value, but no smell and no visual problems 
- 2 transformers of 3 are not value, but no smell and no visual problems

What do you think ? 🙂

Thank's a lot for your answer

E(
Eskobar (archived2)
Bronze
14 posts
Posted October 28, 2020 at 09:26 GMT
#2145983
Nobody knows about this failure?

Can someone tell me if the service manual is offered complete (sliver member) , with measurements of all components?

Guy
Guy
GoldModerator
4528 posts
Posted October 28, 2020 at 10:20 GMT
#2145984

The full Mk2 service manual is available, but I have had a quick glance through and it is mainly concerned with 'fault flow charts' (with test measurements) which then tell you which module/PCB to replace.

Thus I think it may help you may identify the fault and faulty board, but not the specific component. 

Location: Warwickshire, UK

My B&O Icons:

BeoCenter-9500.png BeoCenter-9500.png
Beoremote-Beo4.png Beoremote-Beo4.png
Beovision-10.png Beovision-10.png
Beotime.png Beotime.png
Beosound.png Beosound.png
Beosound-Explore.png Beosound-Explore.png
Beosound-Essence.png Beosound-Essence.png
Beoplay-P2.png Beoplay-P2.png
Beoplay-M3.png Beoplay-M3.png
Beoplay-H4.png Beoplay-H4.png
Beoplay-H3.png Beoplay-H3.png
Beoplay-Form-2i.png Beoplay-Form-2i.png
Beoplay-Earset.png Beoplay-Earset.png
Beoplay-A2.png Beoplay-A2.png
E(
Eskobar (archived2)
Bronze
14 posts
Posted October 28, 2020 at 19:48 GMT
#2145985

Hi,

Thank's a lot for your answer, but I have the same service manual. I have found fault... Thyristors are changed in the PCB 999 : The motherboard. But I don't have inverter measurements... Nothing serial... Inverters are problems...

It's impossible to change inverter without measurements...

92
928gts
Bronze
50 posts
Posted April 12, 2021 at 19:34 GMT
#2145986

Hi!

Did you resolve this?

 

Br Christian

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