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Aussie
My Sharp Zaurus C860 arrived during the week, and pdaXrom was installed as per: http://www.pdaxrom.org/index.php?showid=2&menuid=1

When I rebooted, the Linux operating system was eye candy at its best, and after a bit of a hack around, the system was shutdown by the command "halt".

A few hours later, I press the ON button and ... nothing but a black screen :-((

After reading all web sites and forums, all that I can do is get into a service menu by holding down keys D+M whilst plugging in the AC/DC charger.

Running through all the hardware checks on this service menu, everything seems to work OK except the battery status is LOW. Multimeter confirms that the battery is now 2.4V, and well below its normal fully charged voltage of 3.7V. However, placing the Zaurus/battery on the charger for several hours just doesn't recharge the battery !

Is the battery or the recharging circuit in the Zaurus faulty, or is there something else that I should be doing ?

Help appreciated.

-- Aussie
lardman
I'm not sure the system should be halted.

What happens if you remove the battery for a bit (10sec - make sure no external power is supplied too) then try starting up (button on the back) - you may have to hold it for a little while. Hopefully you'll boot again.

It's possible that the charging is controlled by the Z hardware (which was powered down when you halted - at a guess). Try charging it once it's come back to life.


Si
Aussie
QUOTE
What happens if you remove the battery for a bit (10sec - make sure no external power is supplied too) then try starting up (button on the back) - you may have to hold it for a little while.


Still dead as a dodo - black screen. The battery is drained down to 2.4V and the Zaurus won't boot up at this low voltage. All I can get is the service menu using the D+M+plug in AC/DC charger sequence. And the battery will not recharge at all whilst in the Zaurus.

I was thinking of trying:
1) charging the battery outside the Zaurus directly from the charger;
2) rigging up an alternative power supply directly to the Zaurus to see if it powers up normally (I know I have to be careful to use the exact specs); and/or
3) borrowing another battery - this is no doubt the safest, but will take a few days.

? comments.

Aussie
Miami_Bob
Try pulling the battery for an extended period of time. Several hours. There have been a couple of reports that I recall on hard to start C860s after full "halts". At least one person reported charging the battery externally.

You might want to try booting with D+M, go to page 2, line 10, Charge, Enter & "left arrow" charging ON (use the "<- BS" key to get back out to the menu).

Be very carefull about running "hardware checks" from the D+M menus! Some (like AGING in the Extra Menu) have been reported to hard brick the Z.

Luck!
Aussie
QUOTE
You might want to try booting with D+M, go to page 2, line 10, Charge, Enter & "left arrow" charging ON (use the "<- BS" key to get back out to the menu).


Thanks - I did this overnight, but the battery still didn't recharge :-((

I have 2 battery chargers - both working normally with the multimeter showing outputs of 5v (positive inside, negative outside).

I also did a NAND flash restore, which didn't help.

What is the "Batt Voltage Adjust" (service menu, page 2, line 6) ?

Aussie
Miami_Bob
QUOTE(Aussie @ Jul 24 2004, 07:44 PM)
What is the "Batt Voltage Adjust" (service menu, page 2, line 6) ?

Aussie

Try -

https://www.oesf.org/forums/inde...=4068&hl=adjust

http://externe.net/zaurus/forum/viewtopic.php?t=620
Aussie
Thanks Miami Bob. Those links were helpful, but they still do not spell out a solution. What I think is happening is ...

There is a battery voltage level kept in memory which is the voltage up to which the charger will charge the Zaurus battery. This should be about 4.2V (the maximum voltage up to which the battery is charged).

It seems that certain actions can erase this voltage from memory, which prevents the battery from charging through the Zaurus circuitry.

The way to rewrite a voltage to memory is through the service menu, battery voltage adjustment - but this will only flash the memory with the voltage that the battery has at that time. If the battery is fully charged, then the memory will be flashed with a voltage that will allow the Zaurus to boot up and run, and the charger will thereafter recharge the battery back up to this level. But if the battery has drained, then any reflashing will only allow recharging back up to this lower level ... In my case, my battery drained down to 2.4v, and so I can only reflash the memory with 2.4v, which is insufficient to boot my Zaurus.

Solution (I hope):

1) Get a new fully charged battery, and do a battery voltage adjustment/reflashing which would then allow recharging to this level.

2) Somehow recharge your existing battery outside the Zaurus (which will require a little creative ingenuity). Then replace the externally recharged battery into the Zaurus and do a battery voltage adjustment.

3) As a variation on 2), you can put your battery in the fridge to gain a small recharge. Then replace it into the Zaurus, do a battery voltage adjustment, and then recharge the battery in the Zaurus to this new higher level. Repeat until the battery voltage adjustment is 4.2v.

I will give 3) a try first, and report back.

Aussie
Aussie
Success !!! .... one Z C860 unbricked :-)))

Everything in my previous post seems true, and is explained in more detail below ...

1) THE BATTERY & CHARGER CIRCUITRY:
The Zaurus has a system to protect its circuitry, which can only be powered directly from the battery (with the excpetion of the service menu). The AC/DC charger charges the battery, and the battery powers the Zaurus circuitry.

There is a voltage level flashed in memory - this should be 4.2v = a fully charged battery. When the battery is fully charged (=4.2v) the AC/DC charger cannot send current through to the battery (preventing overcharging and damage to the circuitry). When the battery voltage drains below this, the AC/DC charger can then recharge the battery, and the LED light will be on continuously. When the battery has charged, then no further current can flow through to the battery, and the LED blinks intermittently.

2) THE PROBLEM:
The problem that arises is that the voltage level which is flashed in memory becomes erased - I have not explored the reasons for this, but it happens. With this erased, then current cannot flow from the charger to the battery, and the battery drains such that the Zaurus won't boot (= bricked). Put in a new battery, and the Zaurus works again for a few hours until this new battery has drained.

3) THE FIX:
Now, there is only one way to flash a new voltage level to memory - via the service menu, which is accessed by holding down the D+M keys whilst pluging in the AC/DC charger. Here on page 2, option 6, is the Battery Voltage Adjustment. The Main Bat AD: is the present voltage of the battery. Flash data: - - is the voltage level stored in the Zaurus memory. You can flash the present voltage of the battery into memory by pressing the [Home] or [S] key. But this will only flash the present battery voltage level, and there is no way of changing this. And if the present battery voltage has drained, then there is not much use in flashing a low voltage into memory - you need to flash a working voltage (preferably 4.2v).

What I did was simply charge my battery outside the my Zaurus by just connecting a wire from the positive centre of the charger to the positive battery terminal, and from the negative outside of the charger to the negative battery terminal. I then monitored the battery voltage level as it charged using a multimeter, and stopped charging once the battery voltage was 4.2v (it charged from 2.4v to 4.2v in about 2 hours).

Then, the fully charged battery was replaced in the Zaurus, and this voltage was then flashed to the memory.

Success ... Zaurus unbricked, and all working perfectly.

I hope this HOW TO can be useful to others with the same problem of the battery not charging, and who suspect that the battery is a dud or the Zaurus circuitry is faulty.

Best wishes from Down Under.

-- Aussie
Omicron
Now added to HOW-To Section:

URL:

http://www.zaurususergroup.com/modules.php...%20not%20charge


Thanks Aussie !!!
cgrieves
Interesting post, unfortunately I think there is still an inherent problem with some Cx60 and this kind of confirms it for me.

My C860 has the charging problem and when I first realised it a few weeks ago I checked the voltage values in the service menu. They were all blank (i.e. ___) so I flashed them using a fully charged large battery, but the problem remained up to a point. The battery would charge up to around 30-40% but no more. I also came to the conclusion that the charger charges the battery while the battery powers the Zaurus, because the battery would charge higher if I removed all the peripherals, memory cards and powereed down the LCD. It would still only charge very slowly though. However I found it would not charge for more than a few minutes if I powered down the Zaurus. So it would seem that the voltage drop due to having the Zaurus running pulls the battery voltage down far enough to allow it to charge to an extent.

This lead me to believe that the Cx60 problem is not so much a charging problem as a voltage measurement problem- and after reading your post I think I have confirmed this. I have an external battery charger and three fully charged batteries. No matter what battery I use, the service menu only registers a maximum MAIN BAT AD: 213 (2.7V) even thought the batteries are fully charged. If I flash the adjustment with this battery I get:

MAIN BAT AD: 213 (2.7V)

Flash Data: 213
Delta: +439

Adjust AD: 213 -> 652
: (4.2V)

To test this I used a small battery for a day or so and let it run down to nearly discharged, then charged it in the Zaurus for about three hours (using the powered-on but screen-off technique). I then plugged my CF wifi card in, VNCd to the Zaurus from my PC over the wireless network to keep it active and then tested how long it lasted. The battery charge as detected by the Zaurus started at 40%, then almost immediately dropped to 10%, but then the Zaurus stayed up for just under 50 minutes with the wifi card active, indicative of a reasonably well charged battery. During those 50 minutes the indicator slowly counted down to 3% when the Z powered off.

This implies to me that the Zaurus had trickle charged the battery to a fairly high level, however the voltage detection circuitry could not measure that voltage correctly, so it thought I had 10% power. In fact the battery was reasonably charged and gave a decent lifespan with a wifi card active.

The only thing I haven't done yet is actually measure the voltage of my batteries. Maybe all three are dead and really only giving 2.7 volts but it seems unlikely.

I may rig up a 4.2 volt power supply, feed it to the battery terminals in the Zaurus and flash the voltage adjustment data and see what happens. Maybe it will revive my Zaurus.
lardman
QUOTE
1) THE BATTERY & CHARGER CIRCUITRY:
The Zaurus has a system to protect its circuitry, which can only be powered directly from the battery (with the excpetion of the service menu). The AC/DC charger charges the battery, and the battery powers the Zaurus circuitry.


Hmm, I'm pretty sure you can run the C machines without a battery in them - just plugged into the external supply (though I'll check again).

In any case an interesting thread.


Si
Aussie
QUOTE
I'm pretty sure you can run the C machines without a battery in them - just plugged into the external supply


No, I just tried to run my C860 from the external supply (AC/DC charger) without the battery in, but it wouldn't run. Put the battery back in, and it runs.

The only thing that I can run without the battery is the service menu.

Cheers from down under,

-- Aussie
cgrieves
Aussie, can you post what battery check values you get in the service menu when using a fully charged battery? (AD, Flash data, delta, adjust AD etc etc). Many thanks.
Aussie
Will do, but it will be in a few days (next weekend) when I have a multimeter again.

What I will do is:

1) charge the battery outside the Zaurus - the multimeter shows that the battery charges to 4.2v quite quickly with my 5.1v, 2.5amp AC>DC charger. Then put the battery in the Z and check the service menu battery voltage adjust readings.

2) run the battery down, and recharge it in the Z until it is fully recharged. Then check the multimeter voltage of this fully charged battery, and the service menu battery voltage adjust readings.

Perhaps others might like to do the above also - all you need is a simple multimeter with positive/negative probes.

-- Aussie
Miami_Bob
QUOTE(lardman @ Jul 26 2004, 05:39 AM)
Hmm, I'm pretty sure you can run the C machines without a battery in them - just plugged into the external supply (though I'll check again).

In any case an interesting thread.


Si

My C860 shows same behavior. No battery, no "normal" power on even using AC. Replace battery, powers on as usual.

NOT good planning on Sharp's part, IMHO without some way to go arround it.

VERY good thread, Aussie. But, are you puting the battery under a load to measure the voltage? I know that AA cells show 1.5v with no load when their voltage under load (like in an HP200LX) is significantly lower. Might be a factor.
Miami_Bob
Aussie -

<< the AC/DC charger can then recharge the battery, and the LED light will be on continuously. When the battery has charged, then no further current can flow through to the battery, and the LED blinks intermittently. >>

This popped up from my back brain just a bit ago.

Do you mean that when your Z is fully charged in normal use, the charging LED *blinks*? The LED on my C860 goes OUT once fully charged. The only time that I have ever seen it -blink- is on AC with no battery installed.

If yours blinks when charged full, that may mean something significant also.
gromituk
QUOTE(Aussie @ Jul 26 2004, 03:24 AM)
...the multimeter shows that the battery charges to 4.2v quite quickly with my 5.1v, 2.5amp AC>DC charger.

I would be careful charging the battery with such a high current - you may well shorten its life considerably.

Very interesting deductions going on on this thread!
ThC
I think it's one of the worst days of my life ...
yesterday when unplugging my charger , I accidentaly inversed the polarity on it (damn third party multipurpose charger) and plugged it in with inversed polarity for ... maybe half a second before relising the light weren't going on and unplugging it... Now the charging light is back when I plug it back wih good polarity but the battery don't seem to charge at all ... I think I've frown the charging circuit in my Z BUT do you think I should/could try this solution anyway ?
If someone experienced the same problem and had to send it back for repair ... how much did it cost ? is there a way to have it fixed by myself/someone else than sharp ?
ThC
Just followed the HOWTO... et voila.. seem to work well now, just used wifi a few minutes and recharged the battery to its initial state,will test more tomorrow ... so it seem the values got lost because of inversing polarity ...

edit : i got wrong and was dreaming too much ... it didn't worked and it won't charge anymore sad.gif ... if someoe could answer my second question plz (can I have it repaired by myself/someone else than sharp ?)
cgrieves
I'd love to be proved wrong, but I reckon there are two types of charging issue:

1) Those who have simply lost their charging parameters in flash memory.

2) Those who actually have a fried charging system.

I think we really need users with and without problems to post their voltage values from the service menu. If people with no charging problems are reading 2.8 volts with a fully charged battery then there's hope.....


Incidentally, I don't know a lot about embedded systems, but it seems to me that if the service menu (which surely is just a program stored in flash memory) can adjust the charging parameters, surely we should be able to write an application that can modify the values outside of the service menu?
Miami_Bob
Have not seen this info mentioned on ZUG. Its important (IMHO) for anyone charging the Sharp EA-BL06 battery by alternative methods.


sbbloom69 posted on "The Zaurus Message Board Forum Index -> Hardware" in the thread "C700 - battery charge problem"

http://externe.net/zaurus/forum/viewtopic....fa3a29b6dc3b75f

----------------Begin--------------------------

You must be very careful with the battery. It is not just a battery. I had a dead EA-BL06 (in my SL-5500) and decided to dissect. I then found a Li-IOn white paper from Panasonic that describes the batteries construction and operation.

The EA-BL06 is actually a Li-Ion battery, a small circuit card with a voltage (or current, I'm not sure) regulator, an in-line fuse, and a thermistor imbeded down in the battery. Yes, all these components are on the small sliver-sized circuit board. The three battery terminals are actually large trace pads on this circuit board. The components are on the other side.

The thermistor is a temperature variable resistor that can be read between the center terminal and the negative terminal. Its purpose is to control the charge current to the battery based on the battery temperature. That's how you can get a full charge in only few hours. The charge current is adjusted high enough to just prevent heat damage. Many laptop batteries have this too.


BTW, I just took meter readings and here's what I got on a brand new, fully charged EA-BL06 battery:

Voltage: from + to - terminals: 4.21 volts DC

Resistance: from 7 to 12 kilo-ohms from the middle terminal to the negative terminal (depends on battery temp).

Resistance from + to - doesn't make much sense on this battery, unless you have 0 volts. If you have 0 volts, the internal fused on the circuit card probabaly blew, and you will then get a very high resistance (100 Kohms to several Mohms). A multimeter in the "resistance" mode actually sends out a small voltage and performs Ohm's law (R=V/I) The meter "knows" the voltage and measures the current. Do the division and you know the resistance. A battery is putting out its own voltage (makes sense!), countering the resistance meter's voltage. Therefore, you can't really read the resistance on a "good" battery. Battery internal resistance can be determined with a bridge circuit, or by connecting a precision resistor and ammeter to the battery and solving the equivalent circuit analysys. You should still get about 7 to 12 Kohms from the thermistor (middle to negative terminal), the colder the battery is the higher the resistance.

Hope this helps. It amazes me that a simple battery is not just a simple battery anymore. It does bum me out that the Zaurus wont' work at all without a functional battery (just the charger plugged in). I verified this with Sharp: No battery, no zaurus.

I'm waiting on a BL-08 to do the mod and give my C700 twice the life. I'll post my results when I get it.
Stu
_________________
Stuart
======
SL-C700 (Dynamism, Sharp ROM), AmbiCom WLAN, 64MB Kingston SD card, RIDATA 256MB CF Card
SL-5500 Sharp Rom, SOCKET LP-E CF LAN, 64MB Kingston SD Card, Various 8, 16, 32MB CF Cards
-----------------End---------------------------

I was curious about the "Li-IOn white paper from Panasonic that describes the batteries construction and operation" mentioned & tracked it down to:

http://www.panasonic.com/industrial/batter...on_Charging.pdf

The paper is titled "OVERCHARGE/OVERDISCHARGE/OVERCURRENT SAFETY CIRCUITS" and dated Aug 2003.

One interesting & useful portion of the paper is the section titled "Battery Pack Block Diagram (Reference Example)"

"The diagram below shows a diagram of a lithium ion battery pack. The battery pack includes the batteries, the safety circuits, and thermistors."



I could not get the post to retain the formatting of a diagram here no matter what I did so will try to add it as an attachment.


"1. The Safety Circuits

1.1 The Controller IC

The controller IC measures the voltage for each cell (or for each parallel battery block) and shuts off a control switch to either prevent overcharging (if the voltage exceeds the specified voltage range) or to prevent overdischarging (if the voltage falls below the specified voltage range). Moreover, the voltage of the control switch is measured on both ends and in order to prevent overcurrent, both control switches are shut off if the voltage exceeds specifications.

1.2 The Control Switches

The control switches usually comprise FET structures, and they turn off the charge or discharge depending on the output of the controller IC.

1.3 The Temperature Fuse (Reference Materials)

If the control switches experience abnormal heating, this fuse cuts off the current (non-restoring).

(NOTE THE "non-restoring"! -- M_B)

2. The Thermistors

The thermistors are included in order to accurately measure the battery temperature within the lithium ion battery packs. The battery or charger measures the resistance value of the thermistor between the Tterminal and the negative terminal and during the charging process, controls the charge current along with controlling until the charge is terminated.


Functions and Performance Required in the Charger (Recommendations)

(1) Charge Voltage

The voltage between the charging terminals should be no more than 4.20 V (Set this at 4.20 V (max) after taking into account fluctuations in power supply voltages, temperature deviations, etc.).

(2) Charge Current

The reference charge current should be 0.7 CmA.

(3) Ambient Temperature of the Battery Pack During Charge

0°C to 45°C (Consult Panasonic if the battery pack is to be used outside of this temperature range).

(4) Low-Voltage Battery Pack Charge

When the voltage per cell is 2.9 V or less, charge using a charge current of 0.1 CmA or less.

(5) Termination of Charging

The system will determine that the battery is full by detecting the charge current. Stop charging once the current has reached 0.1 CmA to 0.07 CmA. Note that there will be some degree of variation for each individual battery.

(6) Charge Timer

A total charge timer and a charge completion timer should be included.

(7) Countermeasures for Battery Problems

Select an overvoltage guard in the power supply so that there will be no excessive voltage applied to the battery even if there is a problem with the power supply".

The paper also includes a detailed section titled "FLOWCHART FOR CHARGING LITHIUM ION BATTERY PACKS" which is highly informative but too complex to reproduce here.


A 2nd useful paper in this series is located at:

http://www.panasonic.com/industrial/batter...Precautions.pdf


None of the OEM lithium ion batteries listed at:

http://www.panasonic.com/industrial/batter...hion/index.html

have the form factor of the Sharp EA-BL06, BTW. They are of the "Cylindrical Type" or the "Prismatic Type - Aluminum Housing". So it appears likely that the EA-BL06 are assembled either by or for Sharp specifically.
cgrieves
I just checked my unit with a multimeter. The Sharp standalone charger puts out close to 5V with no battery inserted. My C860 puts out 2.4 volts across the same terminals. Either this voltage ties in with the voltage set in the battery adjustment section in the service menu (i.e. the voltage we're setting is in fact a charge voltage, not a battery voltage), or the charging system truly is fried and will never put out enough voltage to fully charge a battery.....

There may be a quick way to resolve whether there is a hardware or firmware issure here. Can someone with a C860 with a known-good charging circuit remove the battery, plug in the Sharp PSU, and measure the voltage between the terminals in the battery bay?
Miami_Bob
QUOTE(cgrieves @ Aug 2 2004, 04:34 PM)
I just checked my unit with a multimeter. The Sharp standalone charger puts out close to 5V with no battery inserted. My C860 puts out 2.4 volts across the same terminals. Either this voltage ties in with the voltage set in the battery adjustment section in the service menu (i.e. the voltage we're setting is in fact a charge voltage, not a battery voltage), or the charging system truly is fried and will never put out enough voltage to fully charge a battery.....

There may be a quick way to resolve whether there is a hardware or firmware issure here. Can someone with a C860 with a known-good charging circuit remove the battery, plug in the Sharp PSU, and measure the voltage between the terminals in the battery bay?

cgrieves -

My C860 has been charging without any problems. I put it on AC then pulled the battery. The AC/charging LED went out as soon as I flipped the battery switch to Unlock.

The voltage (good digital multimeter) + to - at the C860 with the switch set to unlock was 0.556 V. When the switch was moved to Lock (still no battery) the AC/Charging LED began to flash & the voltage went up to 2.386 V.

I do not have a stand alone charger so can't give any info on that.

I'm curious as to the voltages put out under the D+M menus with & without charging enabled, but I a bit chicken of possibly frosting my charging circuits by turning charging on in D+M without a battery in place. I think that I'll leave THAT test up to someone else.

But your 2.4 V looks like an acceptable value based on my own working system.
Miami_Bob
cgrieves -

The Panasonic charging flow chart starts with a battery pack insertion check. I suspect this is done by checking the thermistor - fuze loop from the (-) to the (T) terminals. Possibly combined with the Lock/Unlock switch?

If no battery pack is detected, the chart loops back to the top & checks again.

If a battery pack is detected (entry point A), it updates & checks a charge total time value T1. If T1 is > 720 min the loop abends with a timeout error. Otherwise, the battery temp is checked and tested to be between an upper & lower max.

If the battery temperature is not in the correct range, the system waits then loops back to (A). If the temp is OK, then "Is voltage check 1 (no load) higher than the charge completion voltage? (4.2 V)".

If > 4.2 V the loop abends with an Overcharge error. In < 4.2 V the next check is "OCV>2.9V". If YES, the system goes into 0.7 CmA charge mode. If NO, into 0.1 CmA charge mode.

In 0.1 CmA charge mode the system either senses the battery voltage > 3V and loops to (A), or a recharge timer causes a loop either to (A) or to the Timeout error.

In 0.7 CmA charge mode, the charging currernt is monitored and compare to two preset values. Based on these measurements and a timer, the system can loop back to (A), timeout or succesfully complete charging.

The voltages mentioned in the paper are 4.2V & 2.9V in the flow chart and the following

1. The Overcharge Safety Function

The charge stops when the voltage per cell rises above 4.30 ± 0.05 V.
The charge restarts when the voltage per cell falls below 4.00 ± 0.15 V.

2. The Overdischarge Safety Function

The discharge stops when the voltage per cell falls below 2.3 ± 0.1 V.
The discharge restarts when the voltage per cell rises above 3.0 ± 0.15 V.


For what its worth. It still doesn't make much sense to me yet.
cgrieves
That cycle does kind of make sense. I just used a faster responding voltmeter on my Sharp standalone charger and the voltage between the terminals ramps rapidly, as if the charger is searching for a battery using the logic loop you describe. However the same two terminals in my C860 do not do this. Whether this is due to the componentry being fried or the flash settings limiting the voltage is, I guess, impossible to tell...

I am going to pull my standalone charger apart tonight, has anyone got any detailed pictures of the inside of a C860? I know it's unlikely but if there's a common component between the PDA and the charger we may at least know which part is responsible, and how much of a nightmare it would be to replace.
Miami_Bob
QUOTE(cgrieves @ Aug 3 2004, 04:52 AM)
That cycle does kind of make sense. I just used a faster responding voltmeter on my Sharp standalone charger and the voltage between the terminals ramps rapidly, as if the charger is searching for a battery using the logic loop you describe. However the same two terminals in my C860 do not do this. Whether this is due to the componentry being fried or the flash settings limiting the voltage is, I guess, impossible to tell...

Does your stand alone charger have 3 terminals like the C860 & battery? If so, you might want to put a resistor between the middle (T) terminal & the (-) of the charger to simulate a battery thermistor (ie - tell it a battery is there). I seem to recall 17k ohm as one of the values in another post of the other related thread here.

Of course, if the stand alone charger is measuring the (+) to (-) voltage &/or the charging current, it probably won't be fooled for long, but the voltage output behavior may give some more useable data.

If I understand the Panasonic paper correctly, the flow chart loops are executed by the external charging hardware while the Overcharge & Overdischarge values seem to refer to the safety control circuits internal to the battery pack itself.

It would be really nice to be able to place a "break out box" between the C860 battery bay terminals and the battery so as to be able to track the charging voltage & current from the C860 interal circuitry. Not sure if this could be done without considerable difficulty, though.
seva
Any updates on the possibly fried charging circuitry, has anyone tried replacing it?

Also, https://www.oesf.org/forums/index.php?showtopic=11539
edi800
QUOTE(seva @ Mar 24 2005, 07:13 PM)
Any updates on the possibly fried charging circuitry, has anyone tried replacing it?


I will try this or nexxt week to fix my SL-C760, so stay tuned.

I have the same problem - lower battery charging voltage, so that battery is not being charged anymore. Caused that by inverting polarization on the DC adapter :-(

I think also that probably those small capacitors on the Z mobo are fried, so they need to be replaced. I found that such small capacitors can be found on some PC mainboards, so the only problem that remains is to find a solder gun capable of soldering such tiny elements :-)
stuffman
Well, my 860 is not charging, but for a different reason entirely. The cute little power adaptor that came with it seems to only want to put out about 2.1vdc to the Z (it's rated at 5vdc output). I can probably go to Rat Shack and get an adaptor to replace it, but I'm quite fond of its easy portability. Has anyone taken one of these apart? It seems like it's just snaped/glued together, and shouldn't be too hard, but it feels like I'm going to break it before it opens. Any help would be greatly appreciated.
cgrieves
Sorry to bring an old thread back from the dead, but it seem this is the only source of info for Cx60 users with truly fried charger circuitry....

Has anyone managed to repair the faulty charging circuit? Alternatively has anyone outside of Japan had their units repiared for a reasonable price?

I'd love to make my C860 usable again so I can ditch this 'orrible IPAQ! smile.gif
Cheers!
ThC
Well, mine have been repaired in japan by the store I buy it from (Brando) ... as it was still under warranty I just had to send it back to brando who then managed to get it repaired and sent it back to me for free ... now it's fried (again) as my girlfriend have done the same error as me , reverting the DC polarity and I'm hoping too to find another way to repair it as it's not under warranty anymore :/
cgrieves
QUOTE(ThC @ May 19 2005, 10:57 PM)
Well, mine have been repaired in japan by the store I buy it from (Brando) ... as it was still under warranty I just had to send it back to brando who then managed to get it repaired and sent it back to me for free ... now it's fried (again) as my girlfriend have done the same error as me , reverting the DC polarity and I'm hoping too to find another way to repair it as it's not under warranty anymore :/
*


Just redirecting anyone with charging problems to this thread:

https://www.oesf.org/forums/index.php?showtopic=11539&hl=

Here's hoping Maslovsky can come up with the repair information!
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