R5-471t black screen no boot

Georgep405
Georgep405 Member Posts: 9

Tinkerer

edited October 2023 in 2020 Archives
Black screen, only blue power light comes on. Tried external monitor, bios boot buttons, disconnecting battery and pressing power button, removing and, etc. Pretty sure it is i/o board or mainboard. Only thing I didnt try is flashing bios off a usb stick. I couldn't find and directions specific to this model. I can download and extract the bios but only see one .exe file. Guess I'm supposed to run it then not click ok to install then rename the file something? What? Then I'll have a new .fd file and flashit.exe file? Then copy these two to the usb stick, insert laptop, then depress esc and fn, while holding down hit power button. Is this correct? I've ordered the two boards and will replace one at a Tim. Thinking I shouldn't flash bios unless the new boards don't work. Laptop only 18 months old. Unacceptable quality. I have 8 year old asus laptop working fine.

Answers

  • JackE
    JackE ACE Posts: 44,905 Trailblazer
    Did you try to turn the lid screen and  monitor screen on with the FN+F6 and FN+F5 toggle key combinations? Did this happen suddenly for no apparent reason? Jack E/NJ 

    Jack E/NJ

  • Georgep405
    Georgep405 Member Posts: 9

    Tinkerer

    Tried external monitor using ft button. Tried Fn f6 as you suggested and many other suggested keys upon powering on. Get blue power light but no display. Disconnected battery, and card, still nothing. RAM integrated. Figure it is mainboard, i/o board, or corrupted bios. 
  • JackE
    JackE ACE Posts: 44,905 Trailblazer
    Did this happen suddenly for no apparent reason? Jack E/NJ 

    Jack E/NJ

  • Georgep405
    Georgep405 Member Posts: 9

    Tinkerer

    Yes. Only thing I didnt try yet is flashing the bios as I hear it can be corrupted. What is the exact procedure for that,?
  • JackE
    JackE ACE Posts: 44,905 Trailblazer
    Almost never successful on UEFI hardware. Unless a Windows update flash failed or the firmware purposely modded, the video failure is usually associated with a CPU/GPU chip failure, not UEFI bootstrapper firmware corruption. Furthermore, the Windows firmware executables are becoming harder to decompress with Windows freeware to extract the correct binary for use outside the Windows environment.

    So the executable usually is run on a different Windows machine, preferrably non-ACER or with a Linux file archive manager. Leave the failure message open on the Windows machine. Then use file explorer to search the C : \users folder for a file "H20*.exe" in a temporary sub-folder. Inside the temporary folder search for a file with a BIN, WPD, ROM or FD file extension, usually but not always isflash.bin. That file must be renamed to SKI2Luffy.FD and then copied to an empty FAT32 formatted USB stick with an LED activity indicator.

    Insert the stick in an R5 port. Plug the charger in. Press and hold the FN+ESC keys. Then while still holding the keys, turn the machine on. Once LED activity starts, you can release the keys. If successful, LED activity will continue for several minutes and the machine will automatically shut down. If not, try another USB port.



    Jack E/NJ
     


    Jack E/NJ

  • Georgep405
    Georgep405 Member Posts: 9

    Tinkerer

    Thanks Jack. I think I understand. I assume this is an UEFI MB so it needs to read the SSD since no firmware on a chip, correct? So it could be a bad SSD and disconnecting the SSD (as one poster receommended) would prevent the UEFI from starting anyway. After watching videos and researching this issue I think it may be the IO board (since it only powers off by pressing the battery reset switch), or if that doesn't solve it, replacing the MB. I tried disconnecting the CMOS battery for awhile, but I suspect these old school techniques are not applicable now.
  • JackE
    JackE ACE Posts: 44,905 Trailblazer
    The UEFI bootstrapper chip actually has firmware needed to initialize all the basic input & output devices (eg KB, basic video adapter, display, RAM, HDD/SSD) just like the old legacy BIOS chips. The UEFI bootstrapper just won't pass this initialization part of the boot process on to the operating system on the SSD for further device refinement unless it can read a trusted file on a small MSDOS-like FAT32 partition on the SSD.

    So, it can theoretically  read an MSDOS-like FAT32 USB stick with the correctly-named FD flash file just like the old BIOS chips by the same cold boot FN+ESC method. The problem is, the UEFI chips FN+ESC flash technique don't seem to be as successful as the older BIOS chips in recovering the video, the latter of which didn't have that great of a track record either (less than about a third of the time). All of which suggests it is neither a UEFI nor BIOS firmware corruption or hardware failure, but more likely an actual CPU/GPU hardware failure.

    Jack E/NJ

    Jack E/NJ

  • Georgep405
    Georgep405 Member Posts: 9

    Tinkerer

    Thanks for the info. I'll let you know it replacing the io board or motherboard fixes the problem. But it also could be a bad ssd, right? This is a disturbing problem, the black screen, since the laptop is only 18 months old and in great shape. I have an 8 year old asus laptop and 4 year old dell that still work perfectly. Very hesitant to buy acer again.
  • JackE
    JackE ACE Posts: 44,905 Trailblazer
    >>> But it also could be a bad ssd, right? >>>

    Very unlikely since a BIOS logo screen should still appear even without a boot drive. However, a bad RAM module might cause the problem. Jack E/NJ

    Jack E/NJ

  • Georgep405
    Georgep405 Member Posts: 9

    Tinkerer

    Installed new i/o card. No difference. Nothing on screen and both the battery light and power light remain solid blue. Off switch still doesn't work. I must insert pin in battery reset hole to turn power off. Tomorrow I'll get the new motherboard and see if that resolves problem. Unfortunately the RAM modules are soldered in so I can't reset or insert new one to see if that is the problem. I have had bad memory modules before but never a bad CPU. But it looks like even that is non-removable. Could it also be a bad MOSFET chip? I've seen techs remove and reinstall new MOSFET and brought MB to life. 
  • Georgep405
    Georgep405 Member Posts: 9

    Tinkerer

    Jack, I saw a thread you wrote last year in same machine with same problem exactly. You referenced a more aggressive method to wake up the system (see your comment below). What is that more aggressive method?
    OK. Disconnnect the coin cell again. Also disconnect battery pack & charger. Then look around the coin cell connectors on the mainboard for two side by side solder bumps that are labelled Jxxx2001. Short the two solder bumps with a screwdriver for about 10 seconds. Then, for good measure, also short the coin cell terminals on the mainboard for another 10 seconds. Then button everything back up including the covers. Try to turn it on again. If still no joy, then we still have another bit more agressive option to try to wake this thing up. Jack E/NJ
  • JackE
    JackE ACE Posts: 44,905 Trailblazer
    Strip all removable unsoldered components from the mainboard. Place it on an aluminum foil cookie sheet. Bake it for 10-15 minutes in a toaster oven pre-heated to 425-450*F.  Also known as a full board solder reflow to try to correct a failure due to a conductor trace break or solder connection as opposed to an IC chip failure. A somewhat less agressive more focussed technique is a heat gun reflow aimed at the suspect chips. Jack E/NJ

    Jack E/NJ

  • Georgep405
    Georgep405 Member Posts: 9

    Tinkerer

    Wow, that does sound pretty aggressive, but based on what I have seen online it makes perfect sense. In my case, I finally got my used motherboard, replaced my old one, it now lives! The only problem I had was removing the copper shield over the heat sink and cpu. Found out it is just barely attached and easy to remove, just used a plastic tool to pop it up and off. Unscrewed the heat sink and then used 99% isopropyl alcohol to remove the old thermal paste, applied new paste, rescrewed the heat sink/fan assembly, MB connectors, and it all worked. Obviously the cpu is a low wattage, laptop variety, and not removeable, so my old MB not of much value. The used MB was $169, cheaper than a new laptop but the unit was only 18 months old. Thanks much for your assistance! You know your stuff.
  • JackE
    JackE ACE Posts: 44,905 Trailblazer
    Congrats on your solution!!! I had a similar issue happen suddenly on an older ACER BIOS laptop that I still used as an everyday Linux workhorse. I was devastated. It completely ruined my day that it happened. Plus a few days thereafter trying to get all my stuff on another machine. It really bothered me. So I was about to try baking the board as a last resort. Then I discovered Aliexpress sold brand new mainboards for my model for less than $25 with free shipping. How could I resist?! Anxiously waited 3 weeks for delivery. Another few hours installing the new board. And I'm using it again right now in this response.  Unfortunately, I think I still feel an urge to try to reflow the old mainboard and re-install it to see if it works. I'm gonna try to control or at least delay my urge.   :)   Jack E/NJ   

    Jack E/NJ

  • Georgep405
    Georgep405 Member Posts: 9

    Tinkerer

    I looked at aliexpress pricing but the prices ranged from $230-$330, all used, and it would probably take at least a month to arrive. Looks like they have good prices for older machines but this is only 2 years old. Wish there was a way to remove the cpu and RAM to test and resell. Maybe I should keep the old part to try the reflow in case this replacement dies.
  • JackE
    JackE ACE Posts: 44,905 Trailblazer
    FYI they warehouse a lot of stuff in KY & CA so delivery times often rival Amazon on some parts that aren't usually available over here even used on ebay. You should save the old board for reflow if the replacement ever dies. Jack E/NJ

    Jack E/NJ