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Acer LA-3581P ICW50 Laptop  Repair

By on October 9, 2020
laptop repair

This repair is about an Acer Aspire 5520G Laptop that suddenly behaved erratic. It started and seconds later reset itself and started again. This production year 2007 made China ICW50 LA-3581P Rev3.0 Laptop in the past was fixed by renewing its battery packs. And it was also successfully hotfixed because previously the LCD screen occasionally showed a black screen after the Laptop had been used without any problem. Next photo shows the Acer mainboard label that is hidden under both DDR2 DRams.

acer laptop repair

What failure the Acer Aspire computer suffered from was quite impossible to determine in this case without a diagnostic tool. Finding the problem here was questionable because there were no Beeps or display messages that pointed in the right direction. Therefore I used my new Qiguan PC test card Kqcpet6-B version 8.0 with Bluetooth Smartphone connection to display the errors it would find. In the past I already had also used old previous version 6.0 without Bluetooth connection. That older PC diagnostic test tool only gave diagnostic answers in the form of Bios error codes after the user had to check in the right Manufacturer’s Bios table to find what it meant. New version 8.0 however directly shows the diagnostic answer on the over Bluetooth to the test card connected Smartphone. So this rules out making any diagnostic user mistake what happens when we look in the wrong Bios list or at the wrong Manufacturer info. These Qiguan Testtools are not exactly cheap but neither are Mobile phones, TV sets, Computers, Sewing machines or Tablets. As all these devices can be tested by the Qiguan hardware and the Smartphone (Android 5.0 or higher) Qiguan App. And when this tool helps us to fix our expensive devices it is worth the money we have spend on this tool.

Next photo shows the mPCIE testcard that I inserted in the Wifi slot of the problem Laptop after first having removed the Wifi card from the Acer mPCIE Laptop slot. The following photo after that shows the active Qiguan test card with the connected mPCIE and its busy green Led.

mpcie test card

mpcie test card qiguan

mpcie test card qiguan computer

Above photo showed the connected Bluetooth transmitting card with bluetooth ok Led and green active Led.

test card table qiguan

Previous photo showed the message I got on my Smartphone from the over bluetooth connected transmitting test card. There are several different Qiguan test cards included for all standard PC slots.

Including the necessary OTG USB cable several flat cables and adapters plus an Android type-C converter that all fit together in a transparent small box.

So after seeing this message I started by checking and flashing the sop8 Bios 28L8005 chip with my TL866 programmer. And I checked its content by comparing it with the also 1024kB original POM117.rom Bios file that was downloaded from the Acer website for the Aspire 5520G. Both were identical and the Bios chip verified fine after it was flashed to make sure it was okay. But after I had soldered the Bios back onto the mainboard topside (it can be found just below the removed keyboard which makes it easier to remove this smd chip) the Laptop was completely dead!

So I removed the Bios chip again thinking it must have been failing somehow. But after rechecking it, nothing was wrong with the 25L8005 Bios chip. Therefore I took apart the Laptop mainboard and started examining the Laptop on component level with my good old trusted friend being my digital multimeter in diode beep test. And I also found an older but good matching schematic with this name “scheme-acer-aspire-as5220-5520-7520-7220-icw50_la-3581p41” to help finding the problem.

I looked at page 41 of this Rev.1.0 schematic. And noticed 4 mosfets on the mainboard that all had a very low resistance between source and drain of only about 8 Ohm. But that short to ground was gone after I removed the Turion AMD 64 x 2 processor from its socket. Page 41 showed those mosfets 36+35 and 42+41. And that must have been the reason for the Laptop no longer working and the fact that the Bios no longer was read by the booting Laptop. Revealing the reason why the Laptop behaved erratic before. Below shows page 41 about the cpu power circuit.

acer laptop circuit diagram

Of course I also had positively measured the presence of 3.3V on pin 8 of the sop8 BIOS chip to gnd pin 4.

acer laptop motherboard repair

how to repair acer laptop

Above 2 previous photos showed the mainboard top side with the BIOS chip in the circle and the 4 measured shorting mosfets in the diamond shaped form. And as mentioned the short circuiting mosfets issue dissolved after the Turion 64 x2 cpu was removed. Plus above the mainboard bottom side is shown with the two DDR2 DRAM slots and the mainboard label.

To make sure nothing had escaped my attention I also had used the good Windows program Anti-Twin to compare the saved Bios firmware with the Bios file I downloaded from the Acer website. And they again were identical. Anti-Twin is a great program in cases when you need to know if your saved/backupped files are identical to the original files. Like when you afterwards get verify errors on your DVD or Bluray burned content and need to know what files are corrupted and fail the test of running okay.

Examining the previously mentioned schematic told me that there was a mainboard upgrade in 2007 why two Bios chips are shown on page 29. And only the U10 was the actual Bios that was present on this revision 3.0 mainboard. Also there is an U4 chip on page 6 of the 42 pages document that measures the cpu temperature to protect it from overheating. My brother bought this Acer in 2009.

Below a photo of the now probably defect Amd Turion Socket S1 TL-60 TMDTL60H AX5DM Cpu with 1M Cache/2.0 Ghz Dual- core Laptop Processor Tl60 Tl 60.


So my brother bought a $5 US dollar used AMD Turion 64 x2 processor hoping it will fix his already about 13 years old Laptop.

Although this Laptop did not gave any helpful diagnostic Beep code or recognizable Acer fault description to point us in the right direction on what the defect was, my brother did notice that the Laptop Led showed a sequence that kept repeatedly showing a short period Led ON, following by 4 longer Led ON period bursts. And at some moments also the internal CD burner/player started to make noise at every Boot start. That kept resetting again and again after only a few seconds switching on, in which the mentioned Led activating sequence was visible. Which gave no clue whatsoever on the failure.

The Qiguan version 8.0 Type B test card diagnostic message showed that the BIOS ecSMDATA and the ecSMCLK connections where always logic low level. And if it was a desktop computer that needed a good diagnostic I also could have used the mSata, the m.2 adapter, the miniPCIe, the B,M and E adapter , the LPC adapter, the EC data cable, or the PCIe x1 or x 16 adapters. Which is easy as most of the diagnostic tests are done fully automated on the Qiguan v.8 Type B tester with the over Bluetooth working Android Test App!

Now we just have to wait until the replacement AMD CPU arrives to know the outcome of this repair. And I do hope that it not was the 3.3V power line or other mainboard fault that was causing this Bios reading problem and why the 638 pins Socket 1 Turion 64 x2 cpu no longer worked. But because the 3.3V voltage was present on the U10 Bios 25L8005 we are safe to say this was not the case or cause here.

And if my conclusion was right it not only fixes a good old Laptop but also proves the advantage of using the new generation Test tools available today. And it again was fixed for a very low price!

There also exist other hardware Testtools for different CPU and Dram sockets that have many small Leds and a small 3V lithium battery holder to test if mainboard and sockets are operating without defects. I also have a few of those but have not yet used them and the S1 socket test board is sadly not one of them. So I ordered this one:

cpu tester

With this socket 1 Laptop 638 pins CPU socket tester we can easily check if all Leds work which in that case tells us that the mainboard socket is not shorted, and every issue is likely only related to the CPU itself and not to the mainboard circuit connections. Here we of course only use this socket1 socket tester when our mainboard is powerless/switched off!

I had ordered the mentioned Qiguan v8.0 Type B diagnostic Tester twice because the first order never arrived. The second time I ordered the same Qiguan PC Tester from another Chinese seller although I also paid about 25% more. I’m glad I did because it turns out to be a very practical piece of equipment. But keep in mind that this practical Tester only works on devices that still (partially) work to examine what is wrong with the electronic circuits!

In the meantime I also contacted seller/engineer William from the Qiguan Pc testers website for more information on the specific Qiguan codes given by the pc tester cards. Specifically for the 6 digit report code my Android Honor H60-L04 Smartphone showed while testing the Acer Laptop. And because I did not get it from the seller he was happy to provide 2 manuals with the Qiguan and Bios Post message codes. Sadly how to read the 6 and 8 digit Qiguan codes on version 8 type B of the Bluetooth diagnostic card is still a small mystery because it seems that these lists only describe the older version 6 pc tester codes.

Maybe we just only need to use the first 2 digits on the left of the old version Qiguan code tables using the ´left 2 digits table’. And the ‘right 2 digits table’ for the 2 right digits in the 6 digit Qiguan code?

So code 477E0C gives us 47 => meaning resetting signal received 3 or more times. And 0C => meaning Quit status failed. And this likely does relate to the short time after boot that the Acer Laptop did reset and started over. And Bios code 88 means in the PHOENIX table ‘Initialize BIOS data area’. On the AWARD table it only says ‘reserved’, and on the AMI Bios table it means ’Main chipset reinitialized after CMOS setup’.

Afterwards as said this Acer IC50 LA3581P laptop didn’t work anymore. Which points to a now completely defect Turion 64 x2 CPU. On still good working computers connected over USB, the Qiguan v8.0 Type B diagnostic Tester card will show some changing and flashing by codes on the Bluetooth connected Smartphone until the codes halt and it will show the message that the CPU, and other parts are okay and the device is working fine. The same ‘all is okay’ message concluded that my over USB to the Qiguan tester connected Samsung TV was working fine too! I however still do not know what Smartphones also can be tested by the new Qiguan tester. And although I had asked about this, I never got any answer. Maybe they couldn’t give any decent answer, or only a disappointing one. And my question about how to read the given 6 digit results on my version 8 type B pc tester wasn’t answered yet either.

The QRP code on the Qiguan pc tester box should help any buyer to the link to download new available Adroid App versions like newest version 6.6. Downloading the new App for not Chinese buyers is sadly close to impossible because it often requires to log in with a Chinese phone number. Therefore the seller had send me the about 5MB working Android App to my email address. And I hope the new v6.6 (For Android phones 5.0 or higher) App will be provided soon. The present App version on previous photos was still old version 5.6.

After the seller send me the new Android version 6.6 it apparently makes the diagnostic tester even better because it doesn’t always show some code but now gives the diagnostic results in clear text. (And apparently there is Lifetime support for all Qiguan buyers!)

Next some photos that show how new version 6.6 looks after the over Bluetooth to the diagnostic card connected Smartphone reads the USB port of my Brother DCP-385C printer.

smart phone qiguan tester

It showed the start page of the diagnostic Android 6.6 App after the phone is connected to the diagnostic card (which is also visible by the now constantly lit Blue Led on the KQCPET6 v8 diagnostic card). The black cable ‘going downwards’ on above photo provides the necessary 5V voltage for the diagnostic card. And the plugged-in microUSB cable goes to the device under test over its USB port.

dcp-385 printer

In this case as said to my over USB connected DCP-385C printer. Shown in above photos.

Of course my printer now didn’t recognize a good memory stick on its USB port why it showed the display message saying to disconnect the USB device and try another device.

If any of the on my Honor H60-L04 Smartphone visible power and signal lines are active they also will show in the diagnostic result. Depending on what port and what diagnostic card is used with the over Bluetooth connected Android App. In this case we however only have connected the USB port of my Brother printer why only the D+ and D- USB signal lines show in the OK result together with a text that says that the cpu, mainboard and memory of the tested device all passed the test!

KQCPET6 v8 diagnostic card

The green Led normally blinks when any data is send while the diagnostic test is active. And the blue Led only blinks when the Bluetooth connection to the (Android 5.0 or higher) Smartphone isn’t active yet.

I also know that my RT809H universal (Nand) programmer is capable in testing communication ports and HDMi connections, and likely much more but I just haven’t found time to check everything yet! But I recently noticed that it not always reads the Bios from most modern Smart television sets over the connected HDMi bus. Like it failed to do with my brother’s Samsung UE50JU6400K television. On which the Samsung TV not even was able to recognize and show the colour test patterns on the selected HDMi port that the RT809H also sends to the TV. Because all HDMi ports simply refused the connected RT809H programmer. And the TV didn’t have a VGA port why only the HDMi ports could be tested and failed to work.

Therefore having more tools and testers to make the life of any repair engineer easier is never a bad thing. Why I recently also made a nifty USB Breakout Box to aid in testing the USB communication

protocols of connected devices as advised in EPE June 2013. And I recently took a 2 year subscription on the new PE magazine because I like what they did with other projects like publishing of the Diode Curve Plotter, that works, although not exactly as described but still is one of the best testers we can build ourselves. (because it only works correctly calibrated if connected to the right Vin input voltage, which won’t be 5V and neither 12V as the article said. But probably around 7,5V DC will do). Compare it if you will to the Peak Atlas DCA75 Pro that also has a PC windows based Curve tracer option and think of it with a portable color screen and you have the Silicon Chip/PE March 2019/2020 Diode Curve Plotter. With the exception that it only tests -ALL sorts of- diodes!

And if you also love electronics and read PE also keep attention on the great things that can be made with the often published Micromite module(s). A universal mini PIC module that programmed in fast Basic can be used with many size modern TFT LCD screens.

Conclusion: After the S1 638 cpu socket tester arrived with the Chinese instructions, it was immediately tested on the defect powered_off laptop mainboard. Next photo shows the result of that socket test:

S1 638 cpu socket tester

Which showed that there was no problem on the S1 638 AMD cpu socket itself. All 76(!) Leds lit up. After that the also received used replacement AMD Turion 64 x2 cpu was inserted but the Acer 5520G Laptop was still completely dead. So this could mean a bad cpu voltage controller or a problem in the mainboard North/Southbridge or in other complex mainboard controller. And replacing those is only possible if we find the exact (older) replacement chips. And the fact that they are mostly bga mounted is another risk of failing in fixing the mainboard problem.

To avoid this we just looked for a used but completely tested working replacement mainboard that saves us not only time but also spending more money on risky used spare parts. And we noticed that this ICW-LA3581p (year 2007) mainboard was plenty available for the price of only five of the mentioned cpu 638 S1 test sockets. And on top of that also with completely free shipping. The defect board still contains several useful spare parts like good mosfets and capacitors that can be used for future repairs. And when the replacement mainboard is installed my brother also has a spare video card, another battery pack and maybe now also a working spare Turion processor for his Acer.

So although these nice diagnostic tools exist they will not help if replacement parts like complex North- or Southbridge controller, or other complex mainboard (voltage) controllers are faulty, and need replacement. And neither do the tools give exact and useful instructions to solve them. The socket testers are available for several cpu sockets and also exist for memory module slots. For very affordable prices each with a lot of Leds and all powered by a simple Lithium CR2032 3V Cell. But as said they probably do not help when the problem originates in any of the complex controllers or voltage regulators.

Knowing these tools exist could help in certain maybe less complex repairs. Anyway, it hopefully made an interesting article.

albert from netherlands

Albert van Bemmelen, Weert, The Netherlands.

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Note: You can read his previous repair article in the below link:



  1. Parasuraman S

    October 9, 2020 at 9:53 pm

    Oh My God! A marathon troubleshooting methods plus ingenious diagnostic tools employed! Vow! What an effort! Many thanks for sharing, though most of it went above my head!

    • Albert van Bemmelen

      October 10, 2020 at 4:23 pm

      The in the article used diagnostic tools showed that they were not as useful as I hoped they would be Parasuraman. For one thing the mostly Chinese instruction manuals for the CPU tester and other sockets, and not getting the right answers on how to read the 6 and 8 digit diagnostic codes from seller or manufacturer weren't helping here either. I guess it somehow went over their heads too? And how useful they really are, we sadly only find out after having bought them.

      • Parasuraman S

        October 10, 2020 at 10:03 pm

        Yes, I agree! I too have burnt my fingers in buying some useless tools! Unfortunately, no guidance will ever come from them!

  2. Aqib Idrees

    October 10, 2020 at 1:49 am

    This is about as useful as a hammer made out of bread

    • Albert van Bemmelen

      October 10, 2020 at 2:18 pm

      Maybe I didn't punch my way out of a wet paper bag in this repair. But just showing how not useful the available not cheap tools often are may be the bread you need to save time and money Aqib.

  3. Mark

    October 10, 2020 at 10:28 am

    Well done Albert - good job!

    • Albert van Bemmelen

      October 10, 2020 at 11:09 pm

      The replacement tested mainboard is on its way and will fix the now completely defect Acer 5520G laptop, Mark.
      In the article I mentioned how difficult it is to log in on Chinese Baidu or other Chinese websites for not Chinese buyers. But good to know is that recently Microsoft launched a free App that fixes this problem and we now easily even without registering by phonenumber are able to log in on those websites! And by adding the Google Translate extension to your browser the Chinese language doesn't have to be a barrier anymore either.

  4. Chaz Heintz

    October 11, 2020 at 12:44 am

    Do you have a better image of the schematic (6-5.JPG) from this article that is clear to read?

    • Albert van Bemmelen

      October 11, 2020 at 7:50 am

      Sure Chaz. It is easy to find with Google on probably more places too. Look here =>

  5. Graeme

    October 11, 2020 at 2:50 pm

    As an old school hardware engineer (many years ago) I find this article very interesting even though a lot went over my head. Back in the day there were not to many diag tools that could be used especially for H/W issues. So now I am thinking, do you invest in the tools which can sometimes be misleading, or go with basic electronic knowledge and order the part you think is faulty, as an engineer,I seem to remember the failures of doing this rather than the successes,although there would of been many successful diagnosis using the basic knowledge.
    Great article showing the thought process and tools of diagnosis.

    • Albert van Bemmelen

      October 11, 2020 at 6:04 pm

      Thank you for your valuable thoughts on using these diagnostic tools or not when we just replace the components we think are at fault Graeme! Maybe the Qiguan PC test card Kqcpet6-B version 8.0 with Bluetooth connection in my article will be of more use if the many PC slots of a Desktop computer are checked? And the CPU socket testers are only useful if we suspect a problem with the mainboard CPU socket. But the Chinese instruction manual of that socket tester on two A4 pages was just Chinese to me and translating it gave wierd results and no answers at all.

  6. Yogesh Panchal

    October 11, 2020 at 9:48 pm

    Hi Albert,
    This types of diagnostic cards are just waste of time because many of them having Programmable ROM on it which works on particular manner for which they have programmed. latest technology motherboards are having more Programmable chips on motherboards,Like Flash BIOS, Super I/O
    and many more they may not communicate with diagnostic card proper way.

    We must use "DSO" for fault finding in proper manner if having reference of signal details of the motherboard.

    Remember while cold testing (Mosfet)remove the additional units fitted on the motherboard like WiFi module ,CMOS Battery, RAM Module and Off course CPU it self specially if you are testing VRM section,else multimeter reading always Misguide us.

    • Albert van Bemmelen

      October 12, 2020 at 12:46 pm

      Thanks for your much appreciated reply Yogesh. I read your recent article about the Super I/O controller. And it probably explains why the seller/manufacturer wasn't able to answer my legit questions about the meaning of the 6 and 8 digit codes he used. I also wondered about the value of the Diagnostic card using the USB port to check if a device is okay. Because if the device is dead it surely won't work anyway, and any message saying that everything works fine is that what I already knew! Maybe I'm still able to fix the defect Acer 5520G mainboard the old way but the tested replacement board will arrive any moment now.

  7. Waleed Rishmawi

    October 14, 2020 at 2:47 pm

    wow. you blow my mind off with all this information and details. thanks for sharing although I agree with Parasuraman way over my head because I only repair laptops with power issue and I will stick that. have a blessed day.

    • Albert van Bemmelen

      October 16, 2020 at 11:06 pm

      From what I've seen you fixed on defect Smartphones I think there is no reason why you should only stick with fixing laptop power issues Waleed! The used components on laptop mainboards are about the same size or even a bit bigger which shouldn't make that much difference. Have a blessed day too!


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