Sony MZ-E900 Service Procedures

[Sargaso]

The E900 Service manual talks about using CD and MO discs during the Test Mode (section 4.1 General, page 7). I can't find any information in the service manual or anywhere else that defines what a CD or MO disc is. I supposed that a MO disc was a magneto optical disc (a Minidisc) but maybe that's wrong. I have no idea what a CD disc is with respect to minidisc maintenance. Anybody done the power adjustments on the E900 or know anything about CD or MO discs? Once you have done the NV reset on this thing it stays in Test Mode forever until you finish the electrical adjustments and these discs seem to be essential to get thru that process.

[sfbp]

I'll tell you if you will tell me how to get INTO service mode, heheh.

Seriously, you need to read up a bit on MD technology. CD is just like a CD. It is the format used by pre-recorded MDs. You need exactly one prerecorded MD to test units. However there are ways to fudge the adjustment and skip that step if you are really desperate.

What did you do? The old solder-bridge trick? Or is there some combination of keys/remotes/buttons that I could not understand from the manual. Mind you, I have an E909.

[Sargaso]

Thanks sfbp for the info.

I used the keystroke method described in the E900 Service manual (page 7 section 4.2.1). However it doesn't work exactly the way its described. It seems you have to have to be playing a minidisc before starting to do the procedure.

So first make sure "Hold" is engaged on the minidisc player itself then start playing a minidisc. Next hold the stop button down on the minidisc player and do the rest of the button pushing on the remote as described on page 7. This process will get into TEST MODE every time on my E900. I just looked at the E909 service manual and its the same procedure. I always wanted to try a commercial minidisc, guess that's next on my "to buy" list. I guess any commercial disc will do regardless of year of manufacture or any other factor?

http://minidisc.org/manuals/sony/service/sony_MZ-E900_service_manual.pdf

Let me know if this works to get your E909 into TEST MODE.

[sfbp]

Hmm, that doesn't make any sense at all........ however I do NOT have the original remote. What model number exactly is the remote?

a. this is the only model that I heard of where having something playing is required. I'm astounded by that

b. with the hold switch (on the unit), the remote still works the device perfectly. So the FF FF RW RW (etc) sequence is causing the track number to change so these commands are actually executed.

c. the remote's hold switch on, absolutely nothing happens. This is by design, I believe, since the hold on the remote works quite differently from the hold on the unit. It merely disables the remote from accepting any commands. At least this is the case with all inline remotes for MD that I have tried.

Maybe I'm missing something, or it's something special about the remote which I don't possess.

Yeah, any prerecorded will do. Be wary not to buy something made by a hobbyist from a MO disk with his own pirate label stuck on. The clearest give-away that it's real is the box they always seem to come in, a slightly reduced DVD case is the best way to describe it. Much bigger than just the case that blank MO disks come in.

Update: never mind, I looked more carefully at the service manual, and the remote (RM-MC11EL) is most likely the missing link. I was sure I had bought one, but I cannot for the life of me lay my hands on it.

[Sargaso]

I don't know why but every time I tried to get into TEST MODE by exactly following the procedure, it did not work. Out of desperation , I tried it while it was playing a MD and it worked.

It didn't make sense to me either but it did work at least in my case. I am using the RM-MC11EL remote.

I'll be sure that the prerecorded MD I get comes in the large plastic case.

[sfbp]

I just arranged to get an RM-MC11EL. I think I was on course to acquire one of these via CL a couple of years back but the deal never took place. Of course via Ebay it cost me extra but compared to some pricing, if the problem is solved that will still be cheaper than trying to get the E909 serviced somewhere else.

If you hang around, I'll be sure to let you know how I get on (I have a Laser Power Meter here) and perhaps after that I might just be able to fix yours for you.

[Sargaso]

That sounds good if I can't do anything with mine. I will be around, I usually check the new posts daily.

I just bid on a prerecorded MD so at least I'll be able to get thru the electrical tests and get out of TEST MODE. I don't really know if this E900 is dying or just out of some adjustment. Before I erased the NV ram, I noticed that there were several error codes (abnormal spindle error, real data error and focus off center) recorded but I attributed them to a mechanical disorder of some kind because if I squeeze the back hing area when starting to play a MD it will most of the time start playing. But if I don't it just rattles around for a while and says NO DISC on the remote.

[sfbp]

Only if it passes

There's a way to trick the firmware into believing it passed. We can probably help with that.

[Sargaso]

I'm going to get a prerecorded MD anyway but does the tricking firmware procedure require dissembling the unit?

[sfbp]

Nope. But you have to find the correct byte to modify, set it to "cd passed", and let the calibration procedure continue.

[sfbp]

Well, I got my RM-MC11EL, and still no dice whatsoever getting the E909 into service mode.

To make matters worse the purchased item has a barely readable display. Ugh! So I think it's time to get serious and see about the OTHER way to get into service mode, namely the solder bridge.

As this will require a significant workstation "with all mod cons", I am going to see about getting organized properly. My present desk really doesn't have room to do this.

Update: now I feel really stupid. More proof of the assertion that if a piece of equipment knows you have the tools and the methods to fix it properly, it fixes itself.

In frustration I switched back to the RM-MC55EL I had been using, and whose display I can, at least, read. Out of idle curiosity I tried the getting-into-service-mode procedure and immediately it worked. I have since repeated that. I can only guess one of two things:

a. Bad contacts on the remote's socket (the little connector with the 4 pins on it or

b. Some other button stuck on or off either on the remote or on the unit (most likely).

Not only does the unit perform flawlessly, but I actually ran the CD and MO tests and it passed.

I admit, I have not taken the time to check the power voltages as per the service procedure. That will take a bit of effort (and fiddling), which I will eventually do. But the final thing I notice is that the motor spins up and down quite noisily, almost as if the motor is a bit sticky, kind of like a computer (CPU) fan. My thoughts are turning to how to lubricate this.

Also, something very weird that someone might comment on. I have two disks, each recorded in LP2. During playback, one of them spins up almost as soon as it has spun down. The other goes 30 seconds or more between activities. It suggests that when playing back the second disk, the battery will last longer.

Any bright ideas as to what's happening here?

[Sargaso]

Good to here that your unit is functioning ok. No idea what's going on the the two LP2 discs. I'm still waiting to receive the factory made MD so I can get through the CD tests and get out of Test Mode on my E900.

[sfbp]

There's a byte at 024, which is the one shown as FF when all tests passed. I recommend you set it to FF and then run the MO test. The reset step clears it. We can exchange more details via PM if u like.

[Sargaso]

I have received the factory MD and gone through the CD test, MO test and have gotten out of test mode. But CD and MO tests fail with some lazer alignment error if I don't pinch the hing area when doing the test. It passes if I pinch it and fails if I don't. Maybe I'll take it apart and maybe accidently correct some mechanical alignment issue during reassembly.

[sfbp]

Sounds at least possible that some screw is loose. (Mind you we all suffer from that here, speaking for myself anyway - you have to be deranged to be messing with these devices).

[sfbp]

I just discovered that your trick of having a disk playing when you try to get into service mode, and run into trouble, actually has wider applicability. I did it on the NH900 I just worked on.

I have no idea why, unless maybe when running some circuits get warm or something weird, affecting the keypress response for getting into SM.

Just for fun, I'm off to try to get into SM on my MZ-EH70 which I could never figure out how to do before.

[Sargaso]

Good luck with your EH70. Fortunately mine has never given me any trouble (knock on wood).

[sfbp]

No luck getting in. Both my EH70's work perfectly (knocking on twin wooden heads, one for each unit) too.

[sfbp]

I finally got my E909 working. About 1/2 an hour ago. Similar symptoms to yours.

The big breakthrough came when realising that you really really must have 1.5 volts (from regulated PS if poss) for the servo alignment tests to work.

[Sargaso]

Good to know it makes a difference. I used a fresh alkaline Duracell AA battery (measures 1.521 volts) when I ran the CD and MO tests. Maybe that's not within acceptable limits.

[sfbp]

It may well be OK. But check to see it really is 1.5 under load ie with everything hooked up. Mine wasn't. I actually had to set the RPS to read 1.6 on its own dial, whereas unloaded I had it set on 1.4 to get the same 1.5 nominal voltage.