Q: Replacing the blu-ray Laser Diode of a PS3

If the unit is well-designed, there should be no need to do anything more than solder it in place.

However, it's likely you'll have to perform a drive-current adjustment. This might require a special test disk and/or test equipment. The service manual should fill you in.

I've got a colleague who replaces many PS3 laser assemblies (I take it you are referring to the optical head which runs on the deck within the drive, not the *actual* laser diode ?) I will ask him what is necessary. Note also that I think I recall him saying that there are two if not three different variants, so make sure you get the right one. I have dismantled a number of these drives to remove discs from PS3s suffering the YLOD condition. Be careful when you replace the drive's top plate, as several bits of disc handling mech, have to engage correctly with other bits on the main body of the drive. Note also that once the top cover is removed, exposing the top mech plate of the drive, the disc clamp just lifts away. It is not retained by anything other than being 'sandwiched' between the mech plate and the cover. When reassembling, it just sits on top of the (should be at that point closed) lifter 'scissors'.

Arfa

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Thanks, I've never really thought about it this way. The unit would have to be designed in a way to make it quick to assemble and I think it would slow things down far too much on the production line if they had to align the laser on each unit. Also, the laser diode for this drive is a Sony patent and is designed for this laser assembly only so I'm guessing a drive-current adjustment won't be required either.

Thanks again for taking the time to reply. Nick

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Hi Arfa,

Thankyou for taking the time to reply but it's the laser diode itself I'm working on replacing. I can replace the laser assembly no problem, however, it's not at all economical given the price of a laser assembly so am trying to see if I can refurbish broken assemblies by replacing the laser diode. :)

Thanks, Nick

In that case, I think you will really struggle to ever get it working again. The laser diode is an *extremely* precision fit in the optics, aligned at the factory in a precision jig. I once experimented with this on CD lasers, with just about zero success. Even if I got it to read again, the playability was poor. Ask anyone who has ever replaced a Pioneer laser just how difficult it is to align the diffraction grating. Gnat's bollock precision doesn't begin to describe how difficult it is to get it right, and that's Grand Canyon versus an alleyway in terms of relative data pit size.

Given that CD optics are 'broken leg' technology, then DVD optics are in 'heart transplant' territory. Blu Ray, as PS3 lasers are, then fall into 'brain surgery' by comparison ... If the laser diode is even a vanishingly tiny amount off-axis, the beams will not pass through the centre of the lens, so the chances of them being reflected back from the disc correctly to hit the pickup diodes are, IMHO, poor at best. Bear in mind also, that it is not necessarily the laser diode that is at fault. Problems with laser assemblies can also be down to contaminated optics - i.e. nicotine on the critical angle mirror - a faulty pickup diode assembly, or faulty tracking / focus coils.

I am surprised that you think that the cost of a replacement optical assembly warrants attempting to do it by this method. According to my oppo, the price of replacement optical heads is quite reasonable, and allows a good margin on the job ...

You might like to look at Sam's stuff on these heads at

and also the material at

which will give you a bit more of an insight into how much precision is involved in these assemblies.

Arfa

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That does indeed look like it requires a lot of precision.

A lens assembly costs upwards of =A325 whereas a replacement laser diode for the 410aca blu-ray drive I can get for =A37. Obviously replacing the laser diode is a fiddly and by the looks of it impossible job; although there are people out there who are managing to do it, maybe they have their own jig or something.

I'll probably give it a go and fail.

Many Thanks, Nick

Actually, I would go with what Arfa says. What I said was "common sense" -- but probably isn't correct.

With respect to production lines... It isn't how "difficult" it is to do something -- especially if the difficulty is reduced by the use of custom fixtures and test equipment -- but by how long it takes. One of the reasons "modern" electronic equipment is so much cheaper is a high level of integration (ie, fewer parts) combined with much less human labor. And if you can get that labor Really Cheap overseas, so much the better.

I do, however, find it hard to believe that laser-diode installation requres extremely precise adjustments. This (to me) indicates poor product design. Of course, I'm not omniscient in such matters.

As for people claiming to be able to do this job, treat the claims with caution. There are many people offering 'guaranteed solutions' to for instance the YLOD problem, and indeed they do appear to work - at least initially. The trick is that they only seem to last long enough to dispose of the unit claiming it to be a 'worker' ...

The minimum independant commercial repair cost for a PS3 is around 80 quid. My friend charges £120 to replace a laser, and he has no shortage of takers. Sony charge 180 quid for a service exchange PS3, and the cost of a new (pre latest slimline version) PS3 is around £300. Non-workers go on eBay for anything up to £90, and working examples for a lot more than that, so I think that there is potentially enough margin in laser replacement to warrant not having to mess around trying to repair the laser assembly - given that the bulk of the cost is the labour you will have already put in to strip the PS3 and its drive. and then remove the laser anyway to attempt the diode replacement ....

Don't forget to be careful not to lose the little bent piece of metal that the Torx screw that holds the top cover goes into. Only valid for Mk1's of course, the screw going into a moulding on Mk2's and 3's.

Good luck. If you do attempt it, do let us know (honestly !!) how it goes, as I am an interested party on PS3 repairs.

Arfa

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I'll definitely give it a go and let you know how it goes, probably won't be for a little while yet as I have a number of PS3s which I have waiting to be sold first.

Thanks both for your replies, I really should remember to use newsgroups more as the people on here just seem much more intelligent and I always get useful replies unlike on most web forums.

Thanks! Nick

The laser diode itself (in my experience) has a flat, unfocused lens. The focusing, grating, etc comes in later. I have successfully replaced laser diodes but as Arfa says, the problem is often not the diode itself, but other problems in the optic path. One symptom of a failing laser diode (on conventional DVD players) seems to be a situation where the unit plays OK for perhaps 15 minutes to 1/2 hour, then starts skipping, pausing, pixelizing, etc. As the laser diode warms up, emission declines, and soon the bit errors exceed the error correction capability of the electronics. Less critical on an audio CD, but seems to reach a fatal level pretty quickly in DVD players, and I assume BD players may be even more critical - though I've yet to have much experience on those.

Mark Z.

I'm not sure that a requirement for precision of assembly, necessarily indicates poor design. Let's take the example of video heads for a moment. The ferrite head chips were mounted in brass carriers that were just screwed to the head drum, so you might imagine that they would be replaceable. However, such was the level of precision that was required to correctly position these heads, it was not possible to do outside of the factory environment, where I guess the job was made staggeringly easy by appropriate positioning jigs, and automated assembly processes. There was actually one company in the UK that did re-head drums, but the machine that they had to do this was very expensive, and required a skilled operator. So, because video head drums required this level of assembly precision, did that make them a bad idea or a poor design ? I don't actually think so.

To be honest, I doubt whether the accuracy required in positioning the actual laser diode comes close to that required for the pickup array, and they manage to do that ok at the factory. As Mark Z suggests further down, all of the critical optics follow the laser diode, and rotational accuracy should not be an issue. Where I feel that you would have to be very careful, is in getting the diode properly on-axis. If this is off by the tiniest amount, the beam will not pass through the following optics at the places that it is designed to. the error will become cumulative, the further you go down the optical path. You might get away with this on a CD laser, but I'm not sure that you would with a DVD laser. Given that the optics of a BluRay laser are further complicated by the precision harmonic filter behind the objective lens, any such error may well put the optical block's performance below the required minimum for reliable operation.

I suppose that it could be argued that the tracking and / or focus servos may be able to compensate, but these servos should be action-neutral, and if the servos have to compensate for a mechanical error in the beam position, by storing a non-neutral compensation value, then this compromises the integrity of the whole system, by restricting the servo range that's left.

Arfa