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

 
Thread Tools Display Modes
Old 09-16-2019, 03:42 PM   #1
jason123
Badcaps Veteran
 
Join Date: Oct 2015
City & State: Reno, Nevada
My Country: USA
I'm a: Knowledge Seeker
Posts: 561
Default Dell U3011 - Troubleshooting the Power Supply board PS-2201-3-HF

Hi folks,
I see many having issues with the U3011 monitor display (Westinghouse guts?)

I have one that would work if I unplug power from wall every once in a while. Was like that for about 3 months - Now, it doesn't turn on at all (front LEDs), but no backlight or other signs of life.

I replaced the Power Supply PS-2201-3-HF board and that took care of the problem.

I'm trying to repair the PS-2201-3-HF board. It has 2 connectors sets (top and bottom)
Bottom set seems to be just 24V and GND with ENA, ADJ, and HDCR

Top Connector, P802, is identical, but P803 has 5, GND, 24_EN

I buttoned up the Monitor so I'm troubleshooting this board on my workbench. To turn all the supplies on, I'm assuming I tie 24_EN to 5V (with a small resistor)?

Do I have to do anything with the ENA and HDCR pins??

Any common failures that anyone can share on this board?
Thanks
Attached Images
File Type: jpg 20190916_143735.jpg (612.9 KB, 42 views)
File Type: jpg 20190916_143748.jpg (864.7 KB, 37 views)
File Type: jpg 20190916_143808.jpg (756.3 KB, 33 views)
jason123 is offline   Reply With Quote
Old 09-17-2019, 08:17 AM   #2
jason123
Badcaps Veteran
 
Join Date: Oct 2015
City & State: Reno, Nevada
My Country: USA
I'm a: Knowledge Seeker
Posts: 561
Default Re: Dell U3011 - Troubleshooting the Power Supply board PS-2201-3-HF

Looks like 24_EN on P803 is not connected to anything. So I'm guessing the 24 V comes on when the "ENA" is tied high.. So I shorted it to +5V (which does come on), but the 24 V never comes up. Voltage across large Cap doesn't change - 164 V DC. Is this a PFC circuit issue? Looks like this uses the Fairchild FAN7529B. Schematic anyone?
Thanks
Attached Images
File Type: jpg 20190917_080614.jpg (664.1 KB, 32 views)

Last edited by jason123; 09-17-2019 at 09:40 AM..
jason123 is offline   Reply With Quote
Old 09-17-2019, 01:30 PM   #3
jason123
Badcaps Veteran
 
Join Date: Oct 2015
City & State: Reno, Nevada
My Country: USA
I'm a: Knowledge Seeker
Posts: 561
Default Re: Dell U3011 - Troubleshooting the Power Supply board PS-2201-3-HF

Ok, update (to myself ) ENA is simply pass through - maybe to turn on the inverter power? I tied 24_EN to 5V, and now the PFC is working and voltage on large cap is 384 VDC. However the 24 V only comes up to 5.2 V.. and gradually drops to 3 and continues to drop. Does the 24V require a load on it?
jason123 is offline   Reply With Quote
Old 09-18-2019, 08:04 AM   #4
jason123
Badcaps Veteran
 
Join Date: Oct 2015
City & State: Reno, Nevada
My Country: USA
I'm a: Knowledge Seeker
Posts: 561
Default Re: Dell U3011 - Troubleshooting the Power Supply board PS-2201-3-HF

I'm not seeing a controller between the 5V to the 24V. Simply a transformer, some diodes and resistors and caps. Is that possible? are they modulating the 5V and transformer turn ratio sufficient to generate 24V then filter? is that it?
jason123 is offline   Reply With Quote
Old 09-18-2019, 10:02 AM   #5
captainKKK
Senior Member
 
Join Date: Sep 2018
City & State: Katy, Texas
My Country: United States
Line Voltage: Low
I'm a: Knowledge Seeker
Posts: 163
Default Re: Dell U3011 - Troubleshooting the Power Supply board PS-2201-3-HF

Did you check that white fuse in your picture? close to R107.

Last edited by captainKKK; 09-18-2019 at 10:04 AM..
captainKKK is online now   Reply With Quote
Old 09-18-2019, 03:17 PM   #6
jason123
Badcaps Veteran
 
Join Date: Oct 2015
City & State: Reno, Nevada
My Country: USA
I'm a: Knowledge Seeker
Posts: 561
Default Re: Dell U3011 - Troubleshooting the Power Supply board PS-2201-3-HF

That is labeled C107 - I know it's a bad photo. I didn't.. I will shortly and let you know. Seems that the PFC circuit is working - Large Cap voltage goes from 164 to 384 VDC.
jason123 is offline   Reply With Quote
Old 09-19-2019, 10:19 AM   #7
jason123
Badcaps Veteran
 
Join Date: Oct 2015
City & State: Reno, Nevada
My Country: USA
I'm a: Knowledge Seeker
Posts: 561
Default Re: Dell U3011 - Troubleshooting the Power Supply board PS-2201-3-HF

Cap C107 checks out.
jason123 is offline   Reply With Quote
Old 09-19-2019, 08:17 PM   #8
captainKKK
Senior Member
 
Join Date: Sep 2018
City & State: Katy, Texas
My Country: United States
Line Voltage: Low
I'm a: Knowledge Seeker
Posts: 163
Default Re: Dell U3011 - Troubleshooting the Power Supply board PS-2201-3-HF

What are the voltages on P802 and 803 when it's turned on?
captainKKK is online now   Reply With Quote
Old 09-20-2019, 06:47 AM   #9
jason123
Badcaps Veteran
 
Join Date: Oct 2015
City & State: Reno, Nevada
My Country: USA
I'm a: Knowledge Seeker
Posts: 561
Default Re: Dell U3011 - Troubleshooting the Power Supply board PS-2201-3-HF

Hi captainKKK... I found a couple of bad solder joints (actually arching as I move the board) so touched those up, and now 24V comes up to 24.67 V.. However, there is a chatter or relay sound (though I can't find a relay on the whole board)- Audio recording attached.. Seems shorting 5 V to 24_EN is too strong. When I use larger resistors the chatter goes away, but the rail only reaches 20 or 21 V. Any idea what resistance I should put between 5 and 24_EN?
Thanks
Attached Files
File Type: rar AudioRecording.rar (133.1 KB, 14 views)
jason123 is offline   Reply With Quote
Old 10-09-2019, 05:56 AM   #10
jason123
Badcaps Veteran
 
Join Date: Oct 2015
City & State: Reno, Nevada
My Country: USA
I'm a: Knowledge Seeker
Posts: 561
Default Re: Dell U3011 - Troubleshooting the Power Supply board PS-2201-3-HF

Any help here is appreciated folks.. I'm still having the "Clicking noise" coming out of the transformer??? I replaced the parallel Cap on the primary, and that didn't fix the issue. I'm thinking maybe internal arching? However I can't find a replacement transformer. Can anyone confirm that this indeed could be coming from transformer?
jason123 is offline   Reply With Quote
Old 10-15-2019, 08:23 PM   #11
Topcat
The Boss Stooge
 
Topcat's Avatar
 
Join Date: Oct 2003
City & State: Salem, MO
My Country: United States
Line Voltage: 240V @ 60Hz
I'm a: Professional Tech
Posts: 13,538
Default Re: Dell U3011 - Troubleshooting the Power Supply board PS-2201-3-HF

Sounds like it to me. I think I have a spare power supply for one of these in the attic, I have one with a broken panel that I've bilked parts out of.
__________________
<--- Badcaps.net Founder & Owner

Badcaps.net Services:

Premade Capacitor Kits
Badcaps.net Capacitor Master List


Motherboard Repair Services


If you've come here in search of replacement capacitors or repair services, please use the links above.
----------------------------------------------
Badcaps.net Forum Members Folding Team
http://folding.stanford.edu/
Team : 49813
Join in!!
Team Stats
Topcat is offline   Reply With Quote
Old 11-04-2019, 11:07 AM   #12
jason123
Badcaps Veteran
 
Join Date: Oct 2015
City & State: Reno, Nevada
My Country: USA
I'm a: Knowledge Seeker
Posts: 561
Default Re: Dell U3011 - Troubleshooting the Power Supply board PS-2201-3-HF

Quote:
Originally Posted by Topcat View Post
Sounds like it to me. I think I have a spare power supply for one of these in the attic, I have one with a broken panel that I've bilked parts out of.
Hi,
thanks for the post.. would love to get my hands on a supply. I can't find a replacement transformer for this board. I search all over the internet and no one seems to carry that part number
jason123 is offline   Reply With Quote
Old 11-04-2019, 09:45 PM   #13
Topcat
The Boss Stooge
 
Topcat's Avatar
 
Join Date: Oct 2003
City & State: Salem, MO
My Country: United States
Line Voltage: 240V @ 60Hz
I'm a: Professional Tech
Posts: 13,538
Default Re: Dell U3011 - Troubleshooting the Power Supply board PS-2201-3-HF

Quote:
Originally Posted by jason123 View Post
Hi,
thanks for the post.. would love to get my hands on a supply. I can't find a replacement transformer for this board. I search all over the internet and no one seems to carry that part number
I'll poke around tomorrow and see if I can locate it.
Topcat is offline   Reply With Quote
Old 11-05-2019, 02:39 PM   #14
Topcat
The Boss Stooge
 
Topcat's Avatar
 
Join Date: Oct 2003
City & State: Salem, MO
My Country: United States
Line Voltage: 240V @ 60Hz
I'm a: Professional Tech
Posts: 13,538
Default Re: Dell U3011 - Troubleshooting the Power Supply board PS-2201-3-HF

Quote:
Originally Posted by jason123 View Post
Hi,
thanks for the post.. would love to get my hands on a supply. I can't find a replacement transformer for this board. I search all over the internet and no one seems to carry that part number
You're in luck, I found 2 of them. Shoot me a PM if you want one.
Topcat is offline   Reply With Quote
Old 12-26-2019, 08:39 PM   #15
harlock
New Member
 
Join Date: Dec 2019
City & State: edmonton
My Country: Canada
I'm a: Knowledge Seeker
Posts: 1
Default Re: Dell U3011 - Troubleshooting the Power Supply board PS-2201-3-HF

Quote:
Originally Posted by Topcat View Post
You're in luck, I found 2 of them. Shoot me a PM if you want one.
Are you parting with the second one? this is my first post so i guess i will be able to pm after this.

thanks
harlock is offline   Reply With Quote
Old 12-26-2019, 09:31 PM   #16
Topcat
The Boss Stooge
 
Topcat's Avatar
 
Join Date: Oct 2003
City & State: Salem, MO
My Country: United States
Line Voltage: 240V @ 60Hz
I'm a: Professional Tech
Posts: 13,538
Default Re: Dell U3011 - Troubleshooting the Power Supply board PS-2201-3-HF

Quote:
Originally Posted by harlock View Post
Are you parting with the second one? this is my first post so i guess i will be able to pm after this.

thanks
Yea, I could be talked out of it.
Topcat is offline   Reply With Quote
Old 10-21-2020, 11:59 PM   #17
blankdisplay
New Member
 
Join Date: Oct 2020
City & State: Vic
My Country: Australia
I'm a: Knowledge Seeker
Posts: 5
Default Re: Dell U3011 - Troubleshooting the Power Supply board PS-2201-3-HF

Gentlemen, apologies for bumping an older thread, but I'm curious if anyone has isolated a common fault with this board?

A little googling and youtube, reveals it seems to be a common fault and paying around $70 to $110 US to import a board is a common fix for those technically minded.

As someone with a soldering iron and multimeter, I'd at least be willing to take a crack at repairing it if there seems to be a common component that gives up.

Any thoughts?

Thanks for your time, it's appreciated!.
blankdisplay is offline   Reply With Quote
Old 10-23-2020, 07:24 PM   #18
momaka
master hoarder
 
momaka's Avatar
 
Join Date: May 2008
City & State: VA (NoVA)
My Country: U.S.A.
Line Voltage: 120 VAC, 60 Hz
I'm a: Hobbyist Tech
Posts: 9,854
Default Re: Dell U3011 - Troubleshooting the Power Supply board PS-2201-3-HF

Quote:
Originally Posted by blankdisplay View Post
Any thoughts?
So would that be the same issue as the O/P's? - i.e. PSU clicking and/or not turning On? If no, you may want to start a new thread, detailing the new/other issues you're having. And whichever the case, some good high-quality pictures of the PSU board uploaded here would be helpful for us to see and try to troubleshoot alongside.
momaka is offline   Reply With Quote
Old 10-31-2020, 05:31 PM   #19
RecentlyShocked
New Member
 
Join Date: Oct 2020
City & State: California
My Country: USA
I'm a: Knowledge Seeker
Posts: 1
Default Re: Dell U3011 - Troubleshooting the Power Supply board PS-2201-3-HF

Anyone looking for U3011 power supply repair tips should take look at this older thread on this forum. It contains two possible repairs.

https://www.badcaps.net/forum/showthread.php?t=56411
RecentlyShocked is offline   Reply With Quote
Old 11-20-2020, 07:45 PM   #20
blankdisplay
New Member
 
Join Date: Oct 2020
City & State: Vic
My Country: Australia
I'm a: Knowledge Seeker
Posts: 5
Default Re: Dell U3011 - Troubleshooting the Power Supply board PS-2201-3-HF

Thanks my reply to this went missing somehow!

I'm off into the other thread, thanks so much for the forum.

Fingers crossed, I posted a heap of pics
blankdisplay is offline   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 04:36 PM.
Did you find this forum helpful?