Re: Help with DVD drive problem


<mydeadpresidents@xxxxxxxxx> wrote in message
news:1147961808.959750.165320@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
First of all, what a nice FAQ this group has put out. So far I haven't
found a better resource.

I have an NEC DVD burner (3540A I think). It's only a few months old
and until recently it's worked perfectly. I took it out of my PC case
and inadvertantly opened the drive door while the DVD was upside down
(power was on). I didn't think anything of it at the time, but since
reinstalling it, it hasn't worked.

Basically, there's a clicking sound, almost like someone clattering
their teeth for a couple seconds. The sounds stops, then repeats a
few times after that. Seems to be seeking or something like that, but
it does the same sound whether or not a disc is in the drive. It even
makes the sound (once) at startup before my OS (xp) loads. Inserting a
disc starts the series of clicks all over again.

Unit has power. Drive door opens and closes normally.

I can't help but feel this is a mechanical problem, as if some sort of
latch, switch or spring has slipped out of place. I unscrewed the
bottom of the drive and took a look but nothing looked out of place to
my untrained eye. I grounded myself an removed some of the circut
boards to get a better look, but again, nothing seemed out of place.
With everything back in place I powered the drive and observed.

I'm not sure if my terms are right, but from inside I can see the
"pickup" move forward along the "rack sled". It gets very close to
what appears to be the "spindle motor" or "spindle platter" and just
before it contacts it stutters and that's the clicking sound. It never
hits, but the motion makes it look like it's tapping several times
before stopping, then it starts over. The actual sound may be coming
from the brass threaded rod that turns and moves the "pickup" forward.
It's very possible that the mechancial problem has nothing to do with
the parts I'm viewing. Nothing appears to be functioning wrong.

Image (not my drive):
http://repairfaq.ece.drexel.edu/sam/d2.gif

One last thing... near the front (door side) of the drive, there's a
kind of... how do I explain. Imagine a circle with two-thirds cut away
and the remaining slice is attached at what would have been the center
of the circle. On this center it is allowed to move clockwise and
counterclockwise to a limited degree. Seems this part is effected
somehow by the opening and closing of the door or the release of same.
The only thing strange about it is that it seems to move too freely.
It looks like something that should require some kind of tension like
that provided by a small spring, but that's just speculation. Again,
an image would be nice.

That's all I know. It's a $60 DVD burner so I can replace it if
necessary. I'm only hoping this is a common enough problem that
someone can identify it and give me a fix. I'm not adept enough to
start testing electronic aspects.

Even if you can't help, can anyone offer a link that shows me some good
internal DVD images? My intuition is that this is something simple.

Thanks if you can help in any way.


At the inboard end of the optical block's track, virtually underneath the
turntable, there will be a switch. Sometimes it's a closed-in switch with an
operating lever, and sometimes, an open contact type, with a protective
clear plastic cover. Its job is to sense when the laser is at the home
position, and inform the system control micro, which will then initiate
focus search and disc spinup. If for any reason, the switch fails to close,
the motor will run on, as you describe, and the drive system will slip
causing the clatter. This is particularly true of drives which use a worm
and pawl drive, as opposed to a set of gears. Usually, the system control
will timeout if it doesn't receive the home signal, and will then try again
to shift the laser home, resulting in the try - break - try again sequence
that you have observed.

My first move would be to get a look on the top side of the deck. You may
well find that something really simple has happened, such as a badly fitted
laser lens cover having fallen off when you tipped it upside down. This may
now be restricting the optical block's movement, and preventing it getting
fully home. You should be able to easily find the home switch, and to move
the laser down its track by rotating the drive by hand. You will then see if
anything is obstructing the correct operation of the switch. Good luck with
it.

Arfa


.

Relevant Pages

  • RE: Black Screen Problem
    ... > can switch over and watch recorded TV, but when you switch back to live TV, ... > the picture is black with sound. ... Once is does happen, the only cure is a reboot, and ... > Disc Drive: DVD Burner ...
    (microsoft.public.windows.mediacenter)
  • Re: New build - halt on ACPI Controller
    ... first I could boot from a cdrom no problem. ... on the hdd from a previous install attempt. ... to do was leave any such drives disconnected from the MoBo and verify ... landed up using the rear panel mains isolator switch to switch it off as ...
    (uk.comp.homebuilt)
  • Re: Looking for comparable sound card
    ... motherboard and the sound was inboard, ... to get a plug and play to use just plugging it to a usb port.. ... Drives Memory Modules c,d ... Primary IDE Channel [Controller] ...
    (microsoft.public.windowsxp.basics)
  • Re: Looking for comparable sound card
    ... motherboard and the sound was inboard, ... to get a plug and play to use just plugging it to a usb port.. ... Drives Memory Modules c,d ... Primary IDE Channel [Controller] ...
    (microsoft.public.windowsxp.basics)
  • Re: Asus P5WD2 Premium board not detecting PATA Devices?
    ... > Problem is when i go into the BIOS, it does not detect the DVD Burner. ... > boot device which I can select a boot priority for. ... > When I boot the system, when the IT8211 Controller detects the IDE ... Also connect all the optical drives to the Primary controller so that ...
    (alt.comp.periphs.mainboard.asus)