electronics, repairs, service manuals and datasheets discussion community for the repairs professionals and technicians
FAQSearchMembersGroupsRegisterProfilePM'sLogin/Out
Philips 190/B6 Monitor OSD Fault.

 
Post new topic   Reply to topic    Electronic equipment repair and service manual search discussion Forum Index -> Computer and office equipment repairs
View previous topic :: View next topic  
Author Message
banger



Joined: 14 Dec 2009
Posts: 4
Location: UK

PostPosted: Mon Dec 14, 2009 12:07 pm    Post subject: Philips 190/B6 Monitor OSD Fault. Reply with quote

Hi all newbie to this board here. Been having some problems with my Philips 190/B6 and the OSD intermittently flashing on and off. I'm an Electronics Eng. but I'm very rusty so need some help in diagnosing the problem.

This is the second monitor with a similar fault, first being replaced under warranty, but second is now out of warranty.

Fault appears to be as if the "OK/OSD" button is being pressed bringing up the OSD on screen sometimes momentarily then going off.

I've already had the monitor apart and cleaned the control board, which cured for 3 months then the problem came back. I have just last night replaced the tactile switch for the OSD button, and again one day in this seems to have cured the problem for now.

But after removing the old switch - testing with an ohm meter shows the switch completely open circuit so I am doubting my current fix.

There appears to be three switches attached to one line, OSD/OK, UP and DOWN, each with a resistor of 47k, 10k and 1k0 respectively, pulling the line down when switch is pressed.

Can anyone point me in the right direction as where to look/test next ?

The service manual for the monitor including schematic can be found at
http://www.taservices.co.uk/download/190b6.pdf

Sorry for long post and thanks in advance.
_________________
Tim Smile
Back to top
View user's profile Send private message
banger



Joined: 14 Dec 2009
Posts: 4
Location: UK

PostPosted: Tue Dec 15, 2009 10:47 pm    Post subject: Reply with quote

Well it's started doing it again, short or replacing all the electolytic caps can anyone have a look at the service manual and suggest what to look at next?
_________________
Tim Smile
Back to top
View user's profile Send private message
jts1957



Joined: 24 Nov 2008
Posts: 2101
Location: Far, Far Away

PostPosted: Wed Dec 16, 2009 7:13 am    Post subject: Reply with quote

Turn unit "On" normally. Unplug the keyboard. If unit still acts up while keyboard is unplugged - keyboard is NOT cause.

Now if you're saying the unit will turn "Off" when you press the "OK/OSD" - then you should be looking at the "power" switch as the one possibly intermittant.
_________________
You're over there, I'm over here.
Back to top
View user's profile Send private message
banger



Joined: 14 Dec 2009
Posts: 4
Location: UK

PostPosted: Wed Dec 16, 2009 10:12 am    Post subject: Reply with quote

Thanks but the OSD switches itself on all by itself then off. Have checked the power switch and it seems ok, could it be a PSU fault?
_________________
Tim Smile
Back to top
View user's profile Send private message
jts1957



Joined: 24 Nov 2008
Posts: 2101
Location: Far, Far Away

PostPosted: Wed Dec 16, 2009 10:28 am    Post subject: Reply with quote

banger wrote:
Thanks but the OSD switches itself on all by itself then off. Have checked the power switch and it seems ok, could it be a PSU fault?


It does this whether the keyboard is plugged in or not ... then keyboard can't be involved check logic/micro/system control, what ever you wish to label it.
_________________
You're over there, I'm over here.
Back to top
View user's profile Send private message
Guest






PostPosted: Wed Feb 24, 2010 3:53 am    Post subject: Reply with quote

Some types philips lcd monitors have the same problems,exp 190s7.the swiths of controlboard under panel failed,this lead this problem.You can replace the switchs with good elements.Or,you can unsorder the switches for emergency.
sorry for my poor english
if you need pictures of the procedure,email me .serveral days ago,I had repaired one with same problem.
Back to top
banger



Joined: 14 Dec 2009
Posts: 4
Location: UK

PostPosted: Wed Feb 24, 2010 4:46 pm    Post subject: Reply with quote

Have replaced the switches a while back and this seems to have cured the problem, thanks for the tip Guest. Wink
_________________
Tim Smile
Back to top
View user's profile Send private message
Guest






PostPosted: Fri Nov 11, 2011 7:38 am    Post subject: Reply with quote

I have got the same problem, but don't know how to repair.

Can anyone help with illustration with photos?

Sa
Back to top
Display posts from previous:   
Post new topic   Reply to topic    Electronic equipment repair and service manual search discussion Forum Index -> Computer and office equipment repairs All times are GMT
Page 1 of 1

 
Jump to:  
You can post new topics in this forum
You can reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


 - Service Manuals Free Download - Prikachi - Service Diagrams

Free TV Schematics Download - HARDW.net - Pinout Master - Jabse Search - Jabse.InK  - Pulsator

Connector Pinout Forum -  - SnimkiOt.com - DNS - Whois  - Poblizo.com :