I've got a Dell C640 laptop that has recently developed the consistent
"Diagnostic Boot Selected" problem on power-up boot. Normally you only get this
by pressing the Fn or "i" button during power up, or by using F12 and purposely
selecting Diagnostic Boot. I get it all the time without pressing anything
extra.

This means you always go to the blue diagnostic screen where it runs the basic
checks of the machine. It never finds anything wrong. The standard Dell
diagnostic partition is gone (it was a wiped lease return machine), and I don't
have the diagnostic CD so I downloaded and set up the C640 diagnostic floppies
and ran everything. Still absolutely nothing wrong. It takes about an hour and
a half to run through all this.

I even used a boot disk with fdisk just to make sure that the regular partition
is the bootable one. Everything looks fine.

After the diagnostic test finishes, or is stopped by hitting the Esc key,
Windows XP Pro boots normally and everything works fine. Warm reboots always
work just fine. The only thing that isn't right is the power-up boot. The
machine never used to do this. It just started sometime in the last few weeks.
It's not crippling, just annoying.

I don't see anything in the bios settings that could cause this. I'm stumped.
Somehow the machine really does seem to think that the Dell Diagnostic Boot is
being selected (not to be confused with the Windows Diagnostic boot which is not
what I'm talking about).

Has anyone pinned this one down? Suggestions? Anyone else with this problem? I
was concerned about the hard drive until the diagnostic spent almost an hour
looking at the hard drive from every possible angle and still could not find
anything wrong.

Curtis Eickerman
Phoenix, AZ

Hi, Curtis.

My name is John, and I am a support analyst at Dell headquarters.
found your post, and wanted to see what I could do to help.

What you're seeing is the Pre-Boot Assessment, and on the C640, ther
are only two ways to launch it. One way, as you noted, is by hitting F1
to get to the boot menu. The other way is to hold the Access Direc
button while turning on the machine.

Given these two options, I highly suspect that there is something wron
with that Access Direct button. Is it mashed in, perhaps?

If you need any help, feel free to let me know:

customer_advocate@dell.com
ATTN: Joh

--
DellCA

On Sep 19, 2:44 pm, DellCA <customer_advoc...@dell.com> wrote:
John,

I am pretty sure the Access Direct "i" button isn't mashed. As a
lease return the machine, it was not set up with the driver for the
"i" button. So after this happened I went to Dell Support, found the
driver, installed it and then used the "i" button to start Internet
Explorer. The button clicks normally and launches Internet Explorer
so I have no reason to believe the button is mashed down. I was
hoping, but no joy. I removed the cover over it and looked and see no
signs of damage either.

I also suspected the "Fn" button but have used it to do "function"
things with the keyboard to eliminate it as well. I did inadvertently
make my boot up screen size real small in the process and had to
figure out how to get it back to normal size again using the Fn key.

In searching the internet I found someone using a D500 (I think) that
had the same problem and eventually cleared it by unplugging and re-
plugging in the cable that feeds the Power Button, the "i" button and
the 3 LEDs (the ones that blink during POST). Why this worked for him
I have no idea and neither did he. For me, getting to that cable
would require a degree of disassembly that may not be warranted. In
the C640 removing the cover over the buttons and LEDs does not seem to
reveal a connector and it looks like keyboard removal is required (not
sure I want to try that just as an experiment). To be honest I did
remove the screws for the keyboard but balked at the step that said
something like "now pry up on the right hand side". Pry? On my
laptop keyboard? Visions of breakage dancing through my head as you
might imagine.

Curtis Eickerman
Phoenix, Arizona

On Sep 20, 3:02 pm, eickr...@aztec.asu.edu wrote:
I've found something that causes the laptop to boot normally but it
makes no sense. If I purposely hold down the Fn key during power up
the C640 boots normally without the "Diagnostic Boot Selected". Of
course this is exactly the opposite of what should happen. I have
separately verified the Fn key is functioning normally by using it to
select the battery status and by using it to toggle the Scroll Lock on
and off as well as using it to select the CDROM eject.

So somehow the Pre-Boot Assessment is being triggered because the Fn
key is NOT depressed during power up.

Curtis Eickerman
Phoenix, Arizona

Very strange, indeed. Holding the Fn key only strengthens my suspicio
that there is something wrong with that -i- key. Mashed in or no, ther
seems to be a malfunction there. I wouldn't recommend disassembling it
though. It is actually part of the motherboard on that model.

If it is that -i- key, a motherboard replacement would cure it fo
sure, but that's a pretty expensive fix for such a small problem.

John
Dell Customer Advocat

--
DellCA

"DellCA" <customer_advocate@dell.com> wrote in message
newsellCA.2xj8k1@no-mx.tabletquestions.com...
John, thanks for looking. At least nothing else seems to be going wrong. It is
only an annoyance and certainly not crippling. For the time being holding down
the Fn during power up or just hitting the ESC key is not a big deal.

Curtis Eickerman
Phoenix, Arizona

Sorry I couldn't be more helpful, Curtis. Without having that unit i
front of me, small failures of that nature are difficult to diagnos
with absolute certainty. If it really is a big deal, I could have i
arranged to have that machine sent to us at Dell headquarters for som
bench testing.

John
Dell Customer Advocat

--
DellCA

On Oct 2, 12:16 pm, DellCA <customer_advoc...@dell.com> wrote:
I work at Texas Childrens Hospital in Houston, Texas. We are a Dell
house and have many laptops. I ran across a Latitude D810 today that
had this very same problem. The F12 key was actually stuck... I had
to use compressed air to clean the keyboard.

"DellCA" <customer_advocate@dell.com> wrote in message
newsellCA.2xu6ji@no-mx.tabletquestions.com...
No problem. It wouldn't be worth the expense to send it in. In the mean time I
experimented a little more. Strangely, holding down quite a number of keys
during Power-On prevents the Diagnostic Boot Selected process. For example,
Shift, CTRL, Fn, Windows Key, Tab, and many letters on the keyboard (though
apparently not all of them) causes a normal boot up. So, preventing the process
is not just the Fn key. The Alt key didn't prevent it. Although holding Alt
while pressing letter keys stops them from working so I am pretty sure the Alt
key is not stuck either.

I could completely map out which keys affect it but it is a little time
consuming as you might imagine powering everything up, shutting down and trying
something different over and over again. I'm suspecting that the keyboard is
just glitching during Power On for reason or reasons unknown.

Curtis Eickerman
Phoenix, Arizona

Curtis-

It is possible that your keyboard is the source of the problem. If yo
can nail that down as the only possibility, the good news is that thos
keyboards are easy to replace and cost very little.

If you need anything, let me know.

John
Dell Customer Advocat

--
DellCA