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How to Fix Your CD Player

By brain in a jar in Technology
Wed Mar 24, 2004 at 10:44:31 AM EST
Tags: Technology (all tags)
Technology

Every year countless CD players get junked because of one simple and easily-fixed problem: they fail to "find" CDs placed in them or they skip. Both of these faults are commonly caused by a misaligned read head.

In this article I provide details of a simple method which I have successfully applied to a number of ailing CD players. I hope that some of you will find it useful and that it will reduce the number of these devices that end up in the trash.


To start with, make sure that your CD player is suffering from the problem that this method is designed to fix. This method is designed to fix a misaligned CD read head. The common symptoms of this problem are:

1. You place a CD in the player, and it spins for a bit but never finds the list of tracks on the CD and returns some kind of error. This problem may occur regularly or intermittently.

2. CDs tend to skip frequently, even if they are clean and in good condition.

So if this sounds like your problem, then this method is for you. You should however bear the following in mind: only attempt to fix the CD player if the fault occurs frequently and is really annoying; i.e. if you are thinking of throwing the CD player away. To carry out the repair you will have to open the case. This will certainly render void any warranty the device might have, so if your player is still under warranty, don't open it. Simply return it to the retailer. Finally, for your safety and that of your equipment be sure to disconnect your CD player and remove any batteries at least a half hour before you start work. Finally, although I have had consistent success with this method, everything you do is at your own risk and is your own responsibility. I provide no guarantee of any nature regarding this method.

Your first job is to open up the case of your CD player. This will be more or less difficult depending on the type of device. If you are lucky and have a Hi-Fi separate type device then it will be pretty simple; if you have a mini or midi-system with a built in CD player this could be trickier. Fixing portable CD players (e.g. a Discman) is probably only for the uber-patient as it is likely to be very fiddly. The main thing required here is patience and a methodical approach. As you remove screws put them somewhere safe; line them up in the order in which you removed them, or make notes of what goes where. You may reach a point where you think you have taken all the screws out but you still can't get into the case. Here, patience is still the key. Check under stickers for hidden screws or clips. Try and work out where the case is held together. Use the minimum force possible at all times.

Now, assuming you have managed to get into the case successfully, and have got access to the CD player we can continue. By now you will probably be able to see the CD tray (the bit that holds the disk) and also some kind of arm which hovers over the disk when the tray is closed. There will usually be a small motor for moving the lens over the disk, and attached to this or nearby there is typically a small circuit board.

On this board, or in any case rather close to the read head there can usually be found a small potentiometer (sometimes referred to as a pot). This will usually be a small square component with a plastic disk on top, and this disk will have a slot which is designed to take a small flat head screwdriver. This is what we will be adjusting.

However, before doing this it is advisable to use an indelible marker pen (magic marker) to mark the current position of the Potentiometer, so that it can be returned to its original position if necessary. With this done then we are ready to start fixing your CD player.

This is essentially a trial and error process. You make a small adjustment to the position of the potentiometer, then try the CD player and see if it is improved. In my experience generally only small adjustments (less than plus/minus 30 degrees of rotation) are usually necessary.

Depending on how comfortable you are working with electrical devices there are different ways of going through this trial and error process. If you are unsure of yourself or particularly safety conscious then will probably want to put the case back on the CD player each time you test it because you will probably have to plug it in to do this. However, as you have probably guessed it is not necessary to put all the screws back in.

If you are a little more comfortable with electrical devices, e.g. you're the kind of person who never puts the sides on the case of their PC, then you may want to do the testing without putting the case back on the CD player. Obviously, this requires a good deal more caution, but it also makes the whole process quicker. While the device is plugged in, be sure to touch only the player's play and stop/eject buttons, unplugging the device again before making any adjustments. Be sure to keep hands and tools away from the player's power supply unit (PSU)/transformer (if you don't know how to identify this then you had better close the case between tries). Also be aware that the PSU can store power for some time, so it is advisable to leave the unit unplugged for a while between attempts, and not to touch the PSU.

After a few attempts it should be possible to find a position of the potentiometer (the little adjustable thing with the slot in the top) where the CD player recognises disks again and plays them without skipping. If, this is the case, then congratulations, you've fixed your CD player. Simply put the case back on and you are ready to rock.

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How to Fix Your CD Player | 71 comments (63 topical, 8 editorial, 0 hidden)
This one happened to me (none / 2) (#7)
by Stavr0 on Wed Mar 24, 2004 at 07:46:31 AM EST

Player dead, no power

There's a fuse inside the case near the power supply. 50 cents later it was working again.

Damn! I wanted to get a CD/DVD/MP3 player to replace it but it still works.
- - -
Pax Americana : Oderint Dum Metuant

Similar advice for PS2 (2.85 / 7) (#9)
by smarkb on Wed Mar 24, 2004 at 09:19:45 AM EST

Ars Technica has a nice guide on doing the same thing for a PS2 when you get read errors. Available here - and it even has pictures.

smark.

Don't forget the cheap/simple problem (2.50 / 4) (#10)
by Xoder on Wed Mar 24, 2004 at 09:32:25 AM EST

The symptoms you mention are also caused by horrifically dirty lenses and can be fixed by a lens cleaner disc.

Lately I've been hearing that god's on our side But rumor has it, there's one on their side too So what I'd like to know is, when it comes down to it, can my god kick their god's ass or what?
Detailed information (3.00 / 5) (#13)
by Stavr0 on Wed Mar 24, 2004 at 10:24:04 AM EST

Sci.Electronics.Repair FAQ - CD Players and CDROMs
- - -
Pax Americana : Oderint Dum Metuant
Unbelievable (2.91 / 23) (#14)
by Mr.Surly on Wed Mar 24, 2004 at 11:45:06 AM EST

That people don't really bother to know what they're talking about before writing about it authoritatively.

There are gross factual errors in this article.  "Why are you such an expert?" you may ask. Because I'm an electronics technician who has fixed hundreds (if not thousands) of cd players.

Top failure reasons:

#1 Dirty lens on laser.  This occurs because most lasers are mounted to point up, to read the bottom side of the disc.  One design (the six-disc changer cartridge) has it the other way around and does not suffer from this problem.

#2 Mechanical. Some older CD players had neoprene belts that would either become brittle and break, lose traction, or would literally melt, leaving a black goo behind.  Many cd players (especially the Aiwa 3-disc turntable changers) are especially sensitive to gear mis-alignments.  Often drive motors for the load/unload or head seek or spindle (spin the disk) motor would fail.

#3 Weak laser.  Laser diodes often lose power over time.  After a while, they're too weak to read the disc properly. This is the problem that this article is actually addressing.  The potentiometer controls laser diode current, and thus the intensity.  However, too much current is bad for the diode and ages it prematurely.  This can be a valid fix for lasers that are dying anyway, as replacement of the laser module is $40-$100 for parts alone.

As far as the factual errors:

... CDs placed in them or they skip. Both of these faults are commonly caused by a misaligned read head. No, they are not.  See reasons #1 and #3, above.  Coarse head alignment is achieved by the head drive motor, the one that moves the head back and forth.  This is not nearly accurate enough to align the laser to the to the (very narrow) tracks on the disc.  Fine alignment is achieved by electromagnets in the laser head that move the lens very slightly along the radial axis of the disc.  When the fine alignment nears it's range, the coarse alignment kicks in and moves the whole assembly slightly.  There is no adjustment for these functions, except maybe on very very old CD players.  Laser focus is obtained via the same method (elecromagnetic) as the fine alignment, except the lens moves closer or farther from the disc.

Finally, for your safety and that of your equipment be sure to disconnect your CD player and remove any batteries at least a half hour before you start work ... Also be aware that the PSU can store power for some time, so it is advisable to leave the unit unplugged for a while between attempts, and not to touch the PSU. Even CD players that plug into the wall are unlikely to have any residual charge in the power supply capacitors after more than 30 seconds, and unless you short it (by wearing a ring when mis-handling the circuit board), you probably wouldn't even notice it if you touched it.  Battery operated cd players don't have (or need) large power supply capacitors, and are safe to touch immediately.

Meh (2.25 / 4) (#19)
by jmzero on Wed Mar 24, 2004 at 12:22:53 PM EST

The video quit working on my DVD player.  Now it's a CD player, and actually a fairly decent one.  I'm throwing it in the garbage - it'll be in the alley behind my house tomorrow.  You can come get it.  Or you can go buy a new DVD player for $40.  

Join the consumer dark side - throw it away and buy a new one.
.
"Let's not stir that bag of worms." - my lovely wife

Disposable electronics. (none / 3) (#27)
by n8f8 on Wed Mar 24, 2004 at 02:07:50 PM EST

Last year I had a rather expensive DVD player stop working. After a little troubleshhoting I figured out the tiny motor that rotated the disc was broken. Tried the internet, radioshack and several electronics catalogs for a replacement. No luck anywhere finding replacement DVD player parts.

So because of a $.50 part my $400 DVD player was useless. The player I bought to replace it was a $40 Sam's Clucb special. No complaints so far.

Sig: (This will get posted after your comments)

You're not realigning anything (3.00 / 13) (#29)
by tzanger on Wed Mar 24, 2004 at 02:51:50 PM EST

You're adjusting the laser power.  Big difference.

Having worked in a repair shop for a few years back in the day I found that most alignment issues with CD/DVD players was due to the anti-backlash spring becoming fatigued -- either replacing the spring or stretching it if a replacement couldn't be obtained tended to fix it.

By far the most common problem with the CD/DVD players was dirty lenses and repairs by people such as yourself who ended up burning out the laser diode module by overdriving the damn thing.  The laser module was probably the most expensive part in the entire unit, too.  

How to fux your CD playet (1.06 / 16) (#44)
by mcgrew on Wed Mar 24, 2004 at 09:10:32 PM EST

Step 1: Find a BFH
Step 2: Grasp BFH firmlyy
Stepp 3: Raise BFH
Stip 4: Smash the fucking CD play er with the BFH
Step 5: Buy new CD player
Step 6: ??????
Step 7: PROPHET!!!!!!


Sorry Folks. (3.00 / 3) (#48)
by brain in a jar on Thu Mar 25, 2004 at 04:46:15 AM EST

Having looked through some of the comments below, it looks like I probably screwed up to some extent. The question is what best to do about it. If the consensus is that it would be a good idea, I could do a rewrite of the article incorporating the new information from the comments, and then ask one of the site admins to delete the original, or at least add a caveat to it saying that the article contains innacuracies and has since been updated.

As to the suggestions by some that this was some kind of elaborate tech troll, you are way off. It was just my honest mistake, I had a method which I knew worked, and I thought I also knew why it worked so I thought I would share. Some folks have pointed out that I should have researched better, which is fair enough, but I thought I already had the answer so I didn't look any further.

Some of the comments mentioned that the commonest cause of the problem described in the article is in fact a dirty lens, and others pointed out that lens cleaning disks are not always a good idea (can cause damage), so is anyone in the know as to the best way to clean cd player lenses.

Basically folks, I am open to suggestions on how to improve this, but if the general opinion is that this article should just be allowed to be lost in the K5 archive then so be it.


Life is too important, to be taken entirely seriously.

Reminds me of my first CD player. (none / 1) (#49)
by bgarcia on Thu Mar 25, 2004 at 07:28:23 AM EST

My first CD player was actually a unit that a friend of mine was going to throw away because it would no longer play CD's. I cracked the case open & took a look. I noticed that there was a drive belt slipping that looked pretty loose.

So I went to the local electronics repair shop and they had a replacement belt (apparently, belts stretch quite often, so they keep a supply on hand). So $1 later I had myself my first CD player.

Good solution for one problem. (none / 1) (#51)
by static on Thu Mar 25, 2004 at 05:18:55 PM EST

However, the description you gave for the problems matched an entirely different problem in my old CD player - the spindle pad isn't gripping the CD hard enough any more so it slips at it spins... woops. :-)

Otherwise, a great article.

Wade.


aiwa cd not spinning (none / 0) (#67)
by guzzi850 on Thu Aug 05, 2004 at 09:51:05 AM EST

I tried your fix. cleaned the opital head but could not find the pot near the head. This is a nsx v2100 shelf system with 3 cd changer mounted on top. optical head located under cd when loaded. I wound up moving the head via the gear rack and the disk spun before i took it apart. a 15.00 box from salvation army that my wife picked up to wire into speakers on our screen porch. Not a real necessary item , the cd, but would be nice to have it working. All else works fine, radio/tape etc. any thoughts?? can email me at freightdog727@yahoo.com if u like thanks scott

So far, so good (none / 0) (#69)
by Nolita on Fri Dec 10, 2004 at 06:44:56 PM EST

Hi, I just wanted to tell you that I tried the tips and I think it worked. That is to say, I opened my portable cd/mp3 player, or rather I pried it open. Then I kept serching for the "pot". Well there was no plastic disk, nor a flat head screw, but I did find a phillips head screw. So I marked a line on both the screw and the area just next to it, then I rotated the screw ever so slightly. Now my CDs are playing, and they're even starting up faster(like new).

I don't think this is for everyone, but if you're like me, and tried everything else(yes I cleaned the discs, yes I cleaned the lens, yes I even tried moving the "head" where the lens resides back and forth). I tried everything else, and they worked for a time, this time none of those things worked. So I hit the net, and found this.

I read the comments too(not a total moron, only a partial one:)). Well I read them and I don't really care what the part is called. I didn't see any of the negative commentators posting their credentials. I mean, saying you're qualified without proving it, well, that's a bit fishy too;).

I just didn't care how fishy or loopy it sounded because I don't have the money to replace my player right now. I figured anything would beat the total crap out of having a $75.00 paperweight(man oh man the prices keep plummeting, a friend of mine just got a cd/mp3 player for $20.00).

Well, so long as it works untill I can get a new one, I'm happy:D.

So thankyou brain in a jar. All I needed was "find the screw on the rectangular doo-hickie"(that's how I eventually translated it) and I am more than happy with the results.

Did I mention I'm happy?



Thanks! (none / 0) (#71)
by tripsey on Sun Dec 19, 2004 at 10:19:25 PM EST

I really appreciate your taking the time to give such a thorough step-by-step description of how to fix the laser position on my boombox CD player, dear Brain in a Jar! I was really about to give up on it, having read many things on the internet about how there is nothing you can do to salvage one once it begins to skip and do weird things. But I took your advice to heart, non-techie that I am. I took my time and found the plastic cover on the square thingymajig, and it absolutely did the trick. Hooray, I saved some space in the landfill! And who cares if it shortens the life of the laser, I was just going to pitch it anyway! Now I wish those former electronics repair folks who have posted here, would tell us where the drive belts are located, etc. and tell us how to make the longer term fixes. Thanks again for taking the time to help out others!

How to Fix Your CD Player | 71 comments (63 topical, 8 editorial, 0 hidden)
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