Badcaps.net Forum
Go Back   Badcaps Forums > Troubleshooting Hardware & Devices and Electronics Theory > Troubleshooting TVs and Video Sources
Register FAQ Calendar Search Today's Posts Mark Forums Read

 
Thread Tools Display Modes
Old 06-28-2020, 10:43 AM   #21
dick_barton
Badcaps Veteran
 
dick_barton's Avatar
 
Join Date: Aug 2015
City & State: Cardiff
My Country: Wales
Line Voltage: 230V AC, 50Hz
I'm a: Hobbyist Tech
Posts: 5,374
Default Re: Philips 37PFL4606 No Power

The 9.8V is just too low and I can't see why. The +5V SB is working so IC905 must be working. Can you measure the voltage across ZD908 and test capacitor C946
__________________
Willing to help but I'm no expert.
dick_barton is offline   Reply With Quote
Old 06-28-2020, 12:02 PM   #22
trunks81
Member
 
Join Date: May 2020
City & State: Waalwijk
My Country: Nederland
I'm a: Knowledge Seeker
Posts: 42
Default Re: Philips 37PFL4606 No Power

Hello

The voltage across ZD908 is 7V, and the cap C946 measure in circuit 48uf and also outside of it.
trunks81 is online now   Reply With Quote
Old 06-28-2020, 12:24 PM   #23
dick_barton
Badcaps Veteran
 
dick_barton's Avatar
 
Join Date: Aug 2015
City & State: Cardiff
My Country: Wales
Line Voltage: 230V AC, 50Hz
I'm a: Hobbyist Tech
Posts: 5,374
Default Re: Philips 37PFL4606 No Power

ZD908 is an 18V zener so with voltage across it appears to be OK.
Can you measure R959. Using meter in diode mode check across D916 in both directions.
Just out of curiosity can you also measure the resistance between the 12V supply pin and chassis and also the 24V pin and chassis of the connector.

Last edited by dick_barton; 06-28-2020 at 12:27 PM..
dick_barton is offline   Reply With Quote
Old 06-28-2020, 12:37 PM   #24
trunks81
Member
 
Join Date: May 2020
City & State: Waalwijk
My Country: Nederland
I'm a: Knowledge Seeker
Posts: 42
Default Re: Philips 37PFL4606 No Power

R959 is 4,7ohm both ways,
D916 is working measure 0.5V and reverse OL
12V to ground is 1Kohm
24V to ground is 2.4Kohm

Last edited by trunks81; 06-28-2020 at 12:39 PM..
trunks81 is online now   Reply With Quote
Old 06-28-2020, 01:07 PM   #25
dick_barton
Badcaps Veteran
 
dick_barton's Avatar
 
Join Date: Aug 2015
City & State: Cardiff
My Country: Wales
Line Voltage: 230V AC, 50Hz
I'm a: Hobbyist Tech
Posts: 5,374
Default Re: Philips 37PFL4606 No Power

There doesn't appear to be an issue on the secondary side of the 12V and 24V supply.
R959 and D916 check out OK.
Need to think about what else could be causing the problem but I'm fairly sure the 9.8V is the issue.
dick_barton is offline   Reply With Quote
Old 06-28-2020, 05:04 PM   #26
budm
Badcaps Veteran
 
budm's Avatar
 
Join Date: Feb 2010
City & State: S.F. Bay area
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Knowledge Seeker
Posts: 37,549
Default Re: Philips 37PFL4606 No Power

What Voltage do you have when measure at the two legs of the cap C946 when 1K resistor is in place and not in place?
__________________
Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956

Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999

Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl

Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/

TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809
budm is offline   Reply With Quote
Old 06-28-2020, 11:28 PM   #27
trunks81
Member
 
Join Date: May 2020
City & State: Waalwijk
My Country: Nederland
I'm a: Knowledge Seeker
Posts: 42
Default Re: Philips 37PFL4606 No Power

When in place iam getting 9.8V and removed 8.1V
trunks81 is online now   Reply With Quote
Old 06-29-2020, 01:04 AM   #28
budm
Badcaps Veteran
 
budm's Avatar
 
Join Date: Feb 2010
City & State: S.F. Bay area
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Knowledge Seeker
Posts: 37,549
Default Re: Philips 37PFL4606 No Power

Quote:
Originally Posted by trunks81 View Post
When in place iam getting 9.8V and removed 8.1V
OK, check the resistance between the two legs of C946 and C922, the meter should show very low resistance at the beginning then it should be in K Ohms range after 10 seconds or so.
Also check the resistance between the positive leg of C946 and C922 in both directions of the probes.

Last edited by budm; 06-29-2020 at 01:06 AM..
budm is offline   Reply With Quote
Old 06-29-2020, 03:01 AM   #29
trunks81
Member
 
Join Date: May 2020
City & State: Waalwijk
My Country: Nederland
I'm a: Knowledge Seeker
Posts: 42
Default Re: Philips 37PFL4606 No Power

Hello


I do not see that the resistance is low in the beginning
C946 = 7.14Kohm, and reverse 56.2Mohm
C922 = 8.2kohm, and reverse 104kohm

Between the positive legs of C946 and C922 51Mohm and reverse 12kohm

Last edited by trunks81; 06-29-2020 at 03:04 AM..
trunks81 is online now   Reply With Quote
Old 06-29-2020, 12:00 PM   #30
dick_barton
Badcaps Veteran
 
dick_barton's Avatar
 
Join Date: Aug 2015
City & State: Cardiff
My Country: Wales
Line Voltage: 230V AC, 50Hz
I'm a: Hobbyist Tech
Posts: 5,374
Default Re: Philips 37PFL4606 No Power

.
dick_barton is offline   Reply With Quote
Old 06-29-2020, 12:20 PM   #31
trunks81
Member
 
Join Date: May 2020
City & State: Waalwijk
My Country: Nederland
I'm a: Knowledge Seeker
Posts: 42
Default Re: Philips 37PFL4606 No Power

What do you mean ?
trunks81 is online now   Reply With Quote
Old 06-29-2020, 11:01 PM   #32
trunks81
Member
 
Join Date: May 2020
City & State: Waalwijk
My Country: Nederland
I'm a: Knowledge Seeker
Posts: 42
Default Re: Philips 37PFL4606 No Power

C920 measure 8kohm and reverse 100kohm
trunks81 is online now   Reply With Quote
Old 06-30-2020, 03:38 AM   #33
trunks81
Member
 
Join Date: May 2020
City & State: Waalwijk
My Country: Nederland
I'm a: Knowledge Seeker
Posts: 42
Default Re: Philips 37PFL4606 No Power

ive have an other board from an 47 inch model.. which has an short in it so the fuse keeps blowing C920 and C915,C922 all measure 270ohm
trunks81 is online now   Reply With Quote
Old 06-30-2020, 05:18 AM   #34
dick_barton
Badcaps Veteran
 
dick_barton's Avatar
 
Join Date: Aug 2015
City & State: Cardiff
My Country: Wales
Line Voltage: 230V AC, 50Hz
I'm a: Hobbyist Tech
Posts: 5,374
Default Re: Philips 37PFL4606 No Power

Quote:
ive have an other board from an 47 inch model.. which has an short in it so the fuse keeps blowing C920 and C915,C922 all measure 270ohm
It would be better to post this as a new thread otherwise it will become confusing.
dick_barton is offline   Reply With Quote
Old 06-30-2020, 06:08 AM   #35
trunks81
Member
 
Join Date: May 2020
City & State: Waalwijk
My Country: Nederland
I'm a: Knowledge Seeker
Posts: 42
Default Re: Philips 37PFL4606 No Power

oke sorry.. any other ideas to get this one running?
trunks81 is online now   Reply With Quote
Old 06-30-2020, 06:18 AM   #36
dick_barton
Badcaps Veteran
 
dick_barton's Avatar
 
Join Date: Aug 2015
City & State: Cardiff
My Country: Wales
Line Voltage: 230V AC, 50Hz
I'm a: Hobbyist Tech
Posts: 5,374
Default Re: Philips 37PFL4606 No Power

At the moment I don't but others may well step in to assist.
dick_barton is offline   Reply With Quote
Old 06-30-2020, 09:00 AM   #37
trunks81
Member
 
Join Date: May 2020
City & State: Waalwijk
My Country: Nederland
I'm a: Knowledge Seeker
Posts: 42
Default Re: Philips 37PFL4606 No Power

Tommorrow i have an working power supply, Hopefully we can reverse engineer it back ti the fault in the other one's
trunks81 is online now   Reply With Quote
Old 06-30-2020, 02:53 PM   #38
budm
Badcaps Veteran
 
budm's Avatar
 
Join Date: Feb 2010
City & State: S.F. Bay area
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Knowledge Seeker
Posts: 37,549
Default Re: Philips 37PFL4606 No Power

Quote:
Originally Posted by trunks81 View Post
Hello


I do not see that the resistance is low in the beginning
C946 = 7.14Kohm, and reverse 56.2Mohm
C922 = 8.2kohm, and reverse 104kohm

Between the positive legs of C946 and C922 51Mohm and reverse 12kohm
OK, they look OK, I was looking to see why you only getting 9V, I need to look further in the circuit.
budm is offline   Reply With Quote
Old 06-30-2020, 03:02 PM   #39
budm
Badcaps Veteran
 
budm's Avatar
 
Join Date: Feb 2010
City & State: S.F. Bay area
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Knowledge Seeker
Posts: 37,549
Default Re: Philips 37PFL4606 No Power

Quote:
Originally Posted by trunks81 View Post
Hello

Between the legs of C907 iam getting 309VDC,

Edit is allready replaced D901,Q902 and R919 because board whas doing notting in the begining
I need clarification about this.
Did you have 5V Standby before replacing those part in the PFC circuit? Were those parts bad?
budm is offline   Reply With Quote
Old 06-30-2020, 03:40 PM   #40
trunks81
Member
 
Join Date: May 2020
City & State: Waalwijk
My Country: Nederland
I'm a: Knowledge Seeker
Posts: 42
Default Re: Philips 37PFL4606 No Power

Those parts were bad. so needed to replace them.. did not measure 5V because fuse kept blowing.
trunks81 is online now   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



Badcaps.net Technical Forums 2003 - 2020
Powered by vBulletin ®
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
All times are GMT -6. The time now is 01:03 PM.
Did you find this forum helpful?