(This is going to sound like a lot of other posts, but read on for more details)

Recently I got my C-860 back from Sharp via Japan Direct, I wanted them to look at the CF port, which may or may not have had a problem, anyhow everything was working fine in regards to charging before that, but after I got it back I couldn't turn the Zaurus on.

I thought this was my battery, so I ordered a new one, Zaurus turned on. After the battery discharged it wouldn't charge anymore, that's when I started looking on the forums about other similiar sounding problems.

I know there are a lot of people reporting problems charging, and have often found odd solutions, like flashing the current state of the battery into the D+M Batt Voltage Adjust menu.

However, it seems like I have a hardware issue, I measured voltage across positive and negative terminals on a normal Zaurus C-860 (my friend's) and mine; here's what I got:

CODE

Normal Zaurus:
   Charge off: 0.4V (or something close to that)
   Charge on: 4.2V

My Zaurus:
   Charge off: 3.0V
   Charge on: 2.5V

What is going on here? Any suggestions? I don't really want to send it back to Japan, because last time it took 3 months?!

For the record, my new battery seems to be fine, when charged in my friend's Zaurus, I can use it just fine until it's drained.

Thanks for reading, as a bonus here's a picture of two C-860s side by side, click for a larger version:


P.S. I meant to post this in the hardware sub-forum, mods feel free to move.

Seva did you ever have any luck getting your unit repaired or replaced??

No, I've been pretty annoyed by this and haven't sent it back yet.

I'll try today.

OK just wanted to keep this thread alive. I have a friend who emigrated from the UK to Japan some years ago, and apparently his girlfriend is a bit of an ogre..... apparently she never keeps receipts or boxes for electronic good, and when something goes wrong with an item, she goes into the shop where she thinks she bought it, throws it at the assistant without box or receipt, does a bit of a strop, and 99% of the time gets the item replaced. Not very ethical I know, but I am going to ship my C860 over to her and get her to try it.

Worth a try.

I am also going to try and get some info on how to get in touch with Sharp Japan.

Let me know if you have any joy with yours!

What kind of power suppply do have? I've had a third party one and changed in a weak moment the polarity ...
It took only seconds to kill the charge modul......

Ulli

I don't know what you were measuring, but battery voltage doesn't drop to 0.4 on a normal zaurus - the battery would have to be completely wrecked to have such a quick loss of charge...

... thanks for reading before posting.

I was measuring the charging circuit not the voltage from the battery.

P.S. JapanDirect didn't even bother to reply when I asked them to help me fix the Zaurus (and sent them a link to this thread), you may want to keep that in mind when you consider whom to purchase your next toy from.

This is easily fixed by replacing a few capacitors. Afriend of mine did that a few times.

Whooooooaaaaaaaaa there cowboy!

I think this is the answer I am looking for.....

Maslovsky, my friend, my best friend.... Is there any chance you can get some more info on what caps we need to replace? I'm have access to decent solder/desolder gear so this might solve all my problems!

There's a reward in it for you (can't think what yet, but we'll think of something!)

Cheers!

Could you please elaborate a little bit more ? Which capacitors ? An electrolytic ones ? If they die in the normal operation modes then shame on Sharp

Sorry for some delay - my rfiend only recently found sometime to take my zaurus apart to try to fix fix sound problem. He told me he was going to take some picctures of the board and provide some instructions about what needs to be fixed for the charging problem...

Allright, cool - we are waiting :-)

Bump!

Don't want this thread to die!

Sorry guys, the pictures will be avaiable soon. My frient went on vacation before I reminded him about the pictures...

My c860 is not turning on. I didn't think this to be a battery issue until I read your post. Even when my Z is plugged into the wall outlet, it will not turn on. Do you think that could still be a battery issue?

The C860 seems to need a bit of charge in the battery before it will turn on, even while on the AC adapter. If you are plugging your adapter in and the charging light is coming on but not charging the battery, then I suspect you may have the charging problem. Trying another battery or using an external charger is the only way to be sure....

Also see if you can get into the service mode (press D & M while turning on).

Thanks for replying. I wasn't able to get into the service mode. Have you had to replace your battery frequently?

I'm not one who likes to replace rechargeable batteries. But hopefully a new battery will solve this problem.

don't want this thread to die neither ^^
my c860 is taking dust ... too bad :/

Yeah, me neither... I have now played with my 860 for a week, and only sad thing is that it doesn't recharge battery...

I was measuring it today for a while. First, I recharged battery back to ~4.2V with external charger. Then I connected all three terminals to 860 with wires to measure voltages. Voltage dropped down to ~3.44V, with or without charger. Even when I measured voltage without battery, it was near that value too. I was thinking to give it a little extra kick from another external power supply, like 4.2V directly to pins, but didn't try that one yet.

Otherwise my 860 is working nice. I can use it as long as I wan't with AC connected, it recognizes charging, turns background light bright, and cacko says that it's charging. But when I unplug AC, charge in the battery drops to the same value it was before connecting AC.

I need to do some investigations, I'm quite sure that charging circuit is not totally dead, but there's something strange.

Oh yeah, and even with fully charged battery, I can't get more than 220 (2.8V) main batteryAD in service menu. This starts to be a challenge to get it working.

Maybe it's those capacitors, need to open it tomorrow.

Edit:

I measured voltages once again. Batteryvoltage drops down to ~3.75V when connected (with or without AC), without battery voltage in terminals is 3.14V. Doesn't matter whether batteryswitch (one that closes the "backdoor", you know.) is on or off, voltage is the same.

Now I'm trying to find suitable screwdriver (why girlfriends never has any decent tools, goddammit) to open my Zaurus.

OK, guys, sorry for some long delay, but here are the pictures of the two fuses that need to be replaces in most cases to fix charging problem:

http://cacko.oesf.org/downloads/fuses/Main...use%20pic_1.jpg
http://cacko.oesf.org/downloads/fuses/Char...use%20pic_2.jpg

Pictures are huge, so I'm only posting links here.

And some explanaition form my friend:

Yes, you were right, charging fuse was burned. Main fuse was ok.

Now I gotta find 630mA fuse in 0603 case.

Edit:
Seems that it's quite hard to find fuse from here in Finland. Farnell doesn't supply 630mA fuse in 0603 (1.6x08mm) case, digikey does, but minimum order is 5000 pieces.

Wickman does manufacture those, so I sent email to them, waiting for reply. 0805 (2x.1.25mm) is little bit too big...

maslovsky: Could you do me a favour and ask your friend, where did he buy those fuses, especially that 630mA one. Since I have gone thru almost every electronic store here in Finland, and I could only find that 5000pcs reel... :|

We took them from another dead Zaurus... Even if we bought them it wouldn't help you since we live in Moscow, Russia

Damn. Well, even coming to visit Moscow would be cheaper than order 5000 pcs reel from USA.

Well, I have to keep on searching. Thanks for your fast reply.

Edit:
Littlefuse seems to manufacture almost that kind of fuses (680mA), and they does provide sample orders too.
Koa Speer also seems to make them. They also have sample order form...

Wow, thanks Maslovsky, I think you have just made an awful lot of clamshell owners very happy indeed, including me! in fact I haven't felt so happy since we won the ashes

I will see what I can find in terms of components. 0603-packaged 2A fuses are very easy to find, but so far I haven't found any 630mA, only 500mA and 750mA.

If anyone finds's a retailer stocking these, please post here and I'll pay to buy a load of them, then we can send them out to whoever needs them. Likewise if I find a source I'll post it here.

Cheers!

Like I said in my previous post, Koa Speers makes them, and they do provide samples for you. Im waiting my shipping early in the next week...

mle

Hi Cgrieves, I was wondering if you've managed to find the fuses - I'm in Woking and desperate to get my hands on them too... I can't for the life of me find anything on the Koa Speers / Littelfuse websites Could you guys let me know where you got the fuses or perhaps post a direct link on where they are on those sites? Pretty pleeeaaaase .

I have an idea, you can buy a normal fuse (a cristal fuse) of 630 ma or 500ma (if you dont find the 630ma fuse).
Break the cristal being carefull to dont miss the conductor, then solder both sides of that conductor to your zaurus where the small fuse goes, taking care to dont touch any other pice of metal or circuit around.

I think that can works!!!

Regards

Nataliya, you can find correct fuses from Koaspeers website:
Products -> Circuit Protection -> Thin Film Chip Fuse (TF) -> And there they are, TF16SN0.63 and TF16SN2.00

You can use the link "order samples" directly, and use those part numbers I gave.

I also got my samples from Koa Speers, I ordered them about ten, so please let me know if you need, I have few extra here which I could send.

mle.

Hi Seinfield, I was thinking this way also when I was quite desperate to find correct fuses. Problem is that those fuses are 0603 size, 1.6x0.8 mm and the layout is quite tight, so adding self-made fuses there may not be easy...

Anyway, I got some samplefuses from Koa Speers, and I also have few extra fuses of both of them, so if there is a need, I can send those extrafuses.

I have no idea what you guys are talking about. Someday I may learn about battery terminals and fuses. Hopefully not anytime soon.

My Zaurus C860 has been a brick for the past 4 months. I ordered a new battery, placed it in, charged it and nothing worked. Today I was thinking of how to get rid of my Zaurus. I came to the forum and was inspired by you all not to give up. It was easier than I thought. I reinserted the battery, plugged in the charger and voila! it came back to life. I am amazed and so happy to have it back. I'm hoping it just needed a new battery.

Maslovsky -- Thank you! That was excellent information. I was nervous about taking my Z apart, but the actual surgery was sort of anti-climatic. Everything went smoothly, all the parts went back together, and the Z is charging as I type. My charging fuse was blown, but the main fuse was OK.

I don't know what I'm going to do with a Zaurus that actually charges batteries!

For anyone else reading this and hoping to fix their charging circuits: KOA Speer sent me 25 of each fuse (more than I asked for) So... I have plenty of extra fuses for both the main and charging fuses (2A and 0.63A). I'll be happy to give some out to anyone else who needs them.

Of course, now that my c760 is fixed, I'll probably be looking for a C1000 or better

I'm glad it helped

Thanks to everyone involved, in particular to maslovsky for the fuse information and dbowden for the information on where to find the fuses. Had I been a bit more adventurous or a bit more experienced with this sort of thing, I could have figured it out much sooner, there are no more than 5-6 fuses total on the entire board, testing each would have taken well under an hour.

I requested samples and after a few weeks I assumed they are not coming in, contacted dbowden through private message and he has mailed me 3 of each fuse, on the same day his fuses came in the samples from KOA Speer came in (12 of each).

Taking apart the Zaurus was fairly easy, however, I don't have much experience in soldering, and while desoldering didn't take that long, actually soldering the tiny (1mm x 0.4 mm or so) fuse was pretty difficult for me (you will need a magnifying glass, I was using a small one from a "Swiss"-army knife).

First thing I did was test each fuse mentioned for continuity, which showed that only the 0.63A was bad, so I only needed to replace that.

Also, the "trick" I ended up using, this may be helpful to those who suck at soldering, is to cut a bit of solder with wire cutters and place them on the board, melt each piece of solder in place a bit, then place the fuse on top and melt each solder chunk while softly pushing the fuse down.

Thanks again everyone, I took a bunch of pictures if anyone needs additional reference, and If anyone needs fuses sent to them faster than 3 week via KOA Speer sample order, drop me a note.

This thread should be stickied and moved to the hardware section!

I did something different, because I suck at soldering even more

I just left the original fuse in place, and glued (not soldered) the replacement fuse ON TOP OF IT. I used a generic Super Glue to do that.

After checking the connection, I found that it is faulty (so that just pushing one fuse on top of another does not result in a good electrical connection), so I added some silver conductive glue (this can be bought in a DYI store) to the ends of fuses.

This 'ghetto' fixing method proved very effective and easy. No soldering was needed, and I didn't even use a magnifying glass.

I'll try to post some pictures of it. In my case only the 0.63A fuse was broken.

Thanks Maslovsky for the pictures and the manual for finding the elements on the Zaurus's board.

Those fuses are much smaller in real life then in those pictures... I blew both the 2A main and the .63A charging. I was wondering if I could get a few of those fuses from anyone that has them and would be willing to send, otherwise I'll have to make a sample order. Edi800, could I see some pics of of the conductive glue repair. I'm not the greatest solderer, and if it doesn't look too bad, that may be how I repair mine. Thanks all in advance.

Private message me your shipping address.

OK, no problem, I'll post the pictures of my fixed setup and of the silver glue. I also thought, when I saw the fuses, that it is next to impossible to solder them
But glueing them on is really easy. :-)

Hi Nataliya, sorry about the lack of reply, I haven't been here for a while!

Anyway I have tried reordering samples from both Littlefuse and Koa from their websites. I did all this before but never recieved confirmation, and nothing ever arrived. If I have any luck then I can easily send a few out to you- I've requested 25 of each fuse from each site. I'll let you know.

Finally I had some time to post the pictures of my 'ghetto' fix:

The best way to open the Zaurus is to use a credit card, pushing it along the edges
of the case.

Afterwards, you should remove a few screws to be able to rise the motherboard.

The 0.63A fuse is under the protective screen that can be seen on this picture:

Mainboard & Protective screen

This picture shows the new fuse already glued to the top of the old broken one:

New fuse on top of the broken one

This is the glue that I used to cover both ends of the fuses:

The silver glue

And this is how it looks just after applying the glue (with the help of a pin):
A little mess after applying the glue

This, as you can see, looks quite awful, but I was able to clean it and make it more professionally looking.

Unfortunately after straightening it out, I was so eager to test the charging of the battery (and it worked!) that I forgot to take the last picture, showing everything in a proper way.

But I hope that it still will be helpful to you :-)

Best regards,
Edi800

Hello - Just read this thread and others with anticipation... I've apparently blown the fuses in my 750 (

Is there anyone in the UK or near enough that has some spare and could send me a couple?

--
Cheers!

To those who PMed me, fuses are in the mail, sorry for the delay.

Edit, Feb 21: Hey, I just mailed another set and I am out of 0.63A fuses (I want to keep a few spares for myself), so I suggest everyone request a bunch of samples from KOA Speer and post here if you are willing to ship them out to other Zaurus users.

WOOT!!! I'm back up and running. I used a two part silver epoxy from the local hobby store and a large magnifying glass. This time I'm going to be a little more careful what I plug into... Thank you all for your help!

Allright! Way to go, man - I'm very happy that it worked for you too :-)

Well I've had no luck getting any samples from Koa or Littelfuse

Koa never answer or anything, and Littelfuse always redirect me to Farnell or RS Components when I order samples, neither of which supply a .680 Amp fuse.

Anyway I gave up decided to buy some 0.5, 0.75 and 2 Amp 0603 fast acting fuses from Farnell. I'll see how I get on with the 0.75 Amp fuse first. I guess if it blows up and destroys the C860 then I won't really have lost much as it's sitting in a cupboard anyway!

Did anyone locate the fuses of a SL-C3000 yet?
Not that I have problems with them, but whenever I have, I'd like to be prepared.

Thanks
daniel

Shouldn't be a problem to locate. Let me know if/when you blow yours, and I'll take a look.
-albertr

Well, at last my C860 is fixed.

My .750mA fuses arrived yesterday and this evening I took the whole thing apart. Breaking the case open wasn't pleasant as I wasn't sure where the clips were. I ended up sliding my thumbnail along the joins.

On mine, the 2A fuse was fine, but the .630mA was blown. When removing the old fuse I was worried that I had broken the solder tag for one end off the PCB. Just to be sure, I added some extra solder to the pad on the new fuse (I lost four fuses just trying to get them out of the packaging!). I then spent about an hour convinced that I had run solder onto the neighboring components as they seemed to have continuity with the fuse. Then I realise that they're probably the components that the fuse protects, so of course they're going to be connected! Just to be sure I took a hi-res photo with my Digicam in macro mode, which convinced me that the soldering was good.

One word of advice to C760/860 owners. I disconnected the wide ribbon cable as I didn't want to stress it. I recommend you don't do this as it's a real b*stard to get back in the socket!

So at last after 2 years of owning a dud Zaurus (it was sold to me as working by an ex forum member!) it's now sitting there happily charging away. Now I've got it working I have no idea what I'm going to do with it, but I guess that's the fun part

Many sincere thanks to Maslovsky in particular for making this repair possible.....

I just got my z apart, and the 630mA fuse is blown. I ordered the fuses from the K.. sg. web site (mentioned on the previous pages), hope they'll arrive in a few weeks.
Anyway, thanks to this topic, there is still hope, that i don't have to send my z to service...
Thanks a lot!

Did you order the fuses to Hungary? Will they actually ship there? If not, PM me your address.