Solved

When pc is shutdown, power indicator LED blinks yellow

Posted on 2008-10-13
24
1,972 Views
Last Modified: 2013-12-11
Hi Experts.  I have a customer who has a Dell e510 and if you select: ( start > shutdown > turn off ) the pc will power off but the LED blinks yellow and you can't turn it on for 20+ minutes.  It doesn't have any random power shutdows or any problem starting back up.  So far, I have these with no success:

Updated the firmware
While the pc was off, unplugged the cord from the back and hit the power button
Tried different plug in the power strip
Tried different power cord (switched with monitor)
Removed all USB and serial devices from the pc and tried to boot up again

Like I said, when the pc is on, there are no problems.  Any ideas??

Thanks.
0
Comment
Question by:samiam41
  • 11
  • 7
  • 4
  • +1
24 Comments
 
LVL 25

Expert Comment

by:SStory
ID: 22703956
Try a different Power Supply

Also is it overheating?  Are the fans working?
0
 
LVL 9

Author Comment

by:samiam41
ID: 22703992
Not sure it's overheating.  The fans are working and the heat is moderate.

I have a spare Dell power supply that I could take over.  Let me cordinate that with the customer.  Would that explain the delay in the computer starting up?
0
 
LVL 6

Expert Comment

by:thebradnetwork
ID: 22704043
Does the computer make a clicking noise right before it reboots because if so it could be your hard drive. If its taking a while to boot off the BIOS you can make the computer give you a detailed boot sequence by pressing ESC i believe.
0
 
LVL 9

Author Comment

by:samiam41
ID: 22704095
Good questions.  First, no clicking sound (man I wish it was that easy).  Second, once you click "ok" from Windows to "turn off" and the computer shuts down, it starts blinking when you hit the power button to turn it back on.  Then it just blinks (which drives you insane if you watch it too long) for 20-30 minutes and finally turns on.  During that time, nothing is displayed on the screen.

I just checked and the spare power supply is 250W, the one in questions is 400W.  I do have a digital battery tester.  I suppose I could use that instead.  Any thoughts?

Is there any kind of setting that controls the delay between the time the pc shuts down and when it can be turned back on?
0
 
LVL 6

Expert Comment

by:thebradnetwork
ID: 22704125
Yes. Sometime the BIOS has some power saving stuff enables on it...disable it all. Then also I would go into my power save under the screen saver part and make sure that the shut down is acctually shutting down and not hibernating or suspending.
0
 
LVL 9

Author Comment

by:samiam41
ID: 22704424
0
 
LVL 26

Accepted Solution

by:
PCBONEZ earned 350 total points
ID: 22704704
Blinking yellow means a power problem.
The fact that you can't shut it down indicates problems with the +5vsb rail.
Try a new PSU first, PSU is most likely but +5vsb problems can also be on the motherboard.

.
0
 
LVL 6

Expert Comment

by:thebradnetwork
ID: 22704879
This program will allow you to check the RAM

http://oca.microsoft.com/en/windiag.asp

If the memory clears (which it is highly unlikely that its RAM but you never know)
If it was the video you probably wouldn't be able to see anything and if you could it would be fuzzy or different colors.
If it was the motherboard or CPU you would probably see the computer lock up in the middle of what you were doing.

My opinion is that it is the power supply but if you are replacing the 400W with a 250W i dont believe that that is going to work over time...you will probably need to get one of equal or greater wattage.
0
 
LVL 6

Assisted Solution

by:thebradnetwork
thebradnetwork earned 50 total points
ID: 22704887
But for short term testing purposes the 250W should be fine.
0
 
LVL 9

Author Comment

by:samiam41
ID: 22704915
Great post gents.  I am scheduling a time to be at the customer's site to check this out.  I will update you all on what I find out.

@ PCBONEZ >>  How in the h3ll did you come up with this?

"The fact that you can't shut it down indicates problems with the +5vsb rail."
0
 
LVL 25

Assisted Solution

by:SStory
SStory earned 100 total points
ID: 22704925
I have had this happen at our work...twice...but in my case it was shutting off unexpectedly.  Both times the light blinked yellow and I replaced the PS and solved the problem.

Well, a 250W might let you test it, but I would recommend bigger for the long haul.  It depends upon how many watts your system requires for each component.  Typically 350W is minimum any more.  400W is really good.

BTW both times it was on a Dell computer.
0
 
LVL 9

Author Comment

by:samiam41
ID: 22704962
That link I posted opened my eyes to a "major" issue with the e510 (possibly other Dell models).  I agree that the 250w won't be a good long term fix.  My concern is whether it would run a proper test.  I have a power supply tester that I have been itching to use.  I plan to take that and the 250w PSU onsite and see what happens.  That link also mentioned the battery on the mobo.  Anyone have any experience with that being the problem?
0
How to run any project with ease

Manage projects of all sizes how you want. Great for personal to-do lists, project milestones, team priorities and launch plans.
- Combine task lists, docs, spreadsheets, and chat in one
- View and edit from mobile/offline
- Cut down on emails

 
LVL 26

Expert Comment

by:PCBONEZ
ID: 22705532
>> @ PCBONEZ >>  How in the h3ll did you come up with this? <<

I'm an electronics tech and I fix PC PSUs (motherboards, LCD screens, and, and) at the component level.
- If you know how to solder, have a multimeter, and preferably access to an O'scope I could probably help you repair it too.
0
 
LVL 26

Expert Comment

by:PCBONEZ
ID: 22705566
The IC chip that allows you to shut-down is powered by +5vsb.
The +5vsb normally comes off a fly-back transformer circuit in the PSU and that's a very frequent source of PSU problems.
0
 
LVL 26

Assisted Solution

by:PCBONEZ
PCBONEZ earned 350 total points
ID: 22705628
If you take a peek inside the PSU look for bloated caps.
The ones that cause problems with +5vsb will be 6 to 8 mm diameter and not near the output wire bundle. (Though the output filter caps can cause problems too.)

0
 
LVL 9

Author Comment

by:samiam41
ID: 22705639
<head spinning>

That is wild.  I am amazed you know that much on that level of detail.  I will be very excited to break that out the next time an issue comes up.  I only have the solder iron and would have to do some digging for the O'scope.  
0
 
LVL 9

Author Comment

by:samiam41
ID: 22705660
Here is an admission few know.  I hate dealing with electricity.  Hate it.  Can I take the cover off of a power supply without killing myself?  I know that may sound dumb but from a man who works primarily with servers and networks, opening up a power supply is one of those "Don't cross the beams" kind of rules built into my instinct.
0
 
LVL 26

Expert Comment

by:PCBONEZ
ID: 22706285
PC tech and Electronics tech overlap but are different.

>> Can I take the cover off of a power supply without killing myself? <<

!!! Do NOT have it plugged in. !!!
The heat-sinks can be energized to 2x line voltage if it has AC power to it.

If you get to actually taking it apart then discharge the one or two huge caps at the input (AC) side. These normally discharge on their own but if something in that discharge path is broken they may be holding a heck of a kick.

Probably 1/2 to 2/3 of bum PSUs can be fixed simply by replacing bad capacitors.
- That's assuming the PSU isn't an el'cheapo model. In el'cheapo's about anything cab blow.

.
0
 
LVL 9

Author Comment

by:samiam41
ID: 22737211
I didn't get a notice that there was a response from an expert.  Sorry about that.

So, if the power supply is not plugged in, I can take it out of the pc.  Then remove the cover and check for bad capacitors?  I have no idea how to "discharge" the caps.  Any ideas?

:-)  Thanks for your help and patience!
0
 
LVL 26

Expert Comment

by:PCBONEZ
ID: 22745588
You will need to carefully remove the PCB from the casing to access the solder side to get to their electrical points.

If you have a Digital Multimeter with a 240-250 VDC or higher range (450 VAC if you live where line voltage is 220v) you can check if they are charged with that.

It is basically the same as shorting a big battery for 5 or 10 seconds.
.
Expect sparks if they are charged significantly and use a HEAVYLY INSULATED metal tool (Rubber Gloves are a good idea too) to short the leads together.

An open end wrench with the right spacing and heavy rubber gloves is what I use.
[Can handle a the current without damaging the tool.]
A screw driver with a wide enough tip works too but the arcing/sparking may melt and damage the tip.

~~~

The odds there will be any voltage left there is very very small.
But if there is some voltage the danger large, so I'm making sure you know.

.
0
 
LVL 9

Author Comment

by:samiam41
ID: 22758739
I remember my first electronics class where we measured the voltage of the outlet in the wall.  It took forever for me to plug that instrument into the wall to get a reading.  I was sure I would be that "one" that future class were told about a student being killed by measuring the electricity.

Is there any other way, like a tool, that will do the same thing as shorting the capacitors?  I am trying to think of what I will need to do while at the customer's house.  If I unplugged the power supply from the wall, then hit the power button on the pc, would that draw out any power left in the capacitors?  Would I need to short them out if I just wanted to open the power supply and see if any capacitors were bad?

Thanks again for your time and patience with this.  I know I must sound like a wuss but I would rather not end up making the news this way.  : )  
0
 
LVL 26

Expert Comment

by:PCBONEZ
ID: 22765240
At some customers house you should do no more than a visual inspection.

-> Unplug it. <-
Open it and inspect for bloated caps with a flash light.
If you need to move wires for visibility and you are worried about getting shocked then use a wooden dowel about 8-10 in long. (Or heat shrink the metal on an old screwdriver.)

Disassembly beyond that is something you do in a shop if your intentions are to trouble shoot the electronics and repair it by replacing parts.

As I said before the caps will only be charged if there is an unusual fault.
You are worrying about this little bit too much.

The 'correct' tool is called a shorting bar.
Usually it's a heavy thick glass bar with a bent copper rod sticking out of the end.
The copper rod has a heavy wire about a foot long attached near the glass handle. The wire has an alligator clip or some kind of a clap at the other end for a safety/secondary ground path.
It's rather difficult to find the real deal.
Most techs modify an old screwdriver for the task.

.
0
 
LVL 9

Author Comment

by:samiam41
ID: 22813060
Very good technical advice.  The customer and his wife are both in real estate and they have taken a beating so I imagine I won't be over there to fix their pc for awhile.

I am going to close this question out and award points based on what I feel would solve the problem and how much I learned from it.  If you have any objections, please let me know.  I don't want anyone to feel jaded.

Thanks again for your help!
0
 
LVL 9

Author Closing Comment

by:samiam41
ID: 31407053
I learned a lot from this question which will also help me with my customers.  Thanks for all of the help and knowledge!  Hope to see you all around.  Take care.

-Aaron
0

Featured Post

IT, Stop Being Called Into Every Meeting

Highfive is so simple that setting up every meeting room takes just minutes and every employee will be able to start or join a call from any room with ease. Never be called into a meeting just to get it started again. This is how video conferencing should work!

Join & Write a Comment

Hello It is a very old trick to use a ram disk in order to boost PC performances, in the past, when in home environments the fastest common devices were floppy disks a part of the very small ram memory available was used to create a virtual hard …
Introduction: When experiencing some peculiar problem with the functioning of your PC, how many times has it happened that you look for a solution and even google can’t help? It could be that you are one of the only few people on earth who ma…
The viewer will learn how to successfully create a multiboot device using the SARDU utility on Windows 7. Start the SARDU utility: Change the image directory to wherever you store your ISOs, this will prevent you from having 2 copies of an ISO wit…
The viewer will learn how to successfully download and install the SARDU utility on Windows 7, without downloading adware.

747 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

10 Experts available now in Live!

Get 1:1 Help Now