Hi @balearis

Yep, I formatted the drive as FAT32 and I have enabled CSM in bios in order to boot from it. Also, I already had disabled secure boot.

A few time ago with an APTIO IV, with AFUWINGUI and a working file,
I changed serial number, w8 serial and turned on backlight, flagging only nr.2 as in the picture......



but I do not want you to do things that I'm not 100% sure on APTIO V, for this it is better to wait for Lost_N_BIOS.....

@noreplyse - thanks for the dump, I'll get you unlocked BIOS shortly. Hopefully the advice above can get your backlight issue fixed, if it does, please send me new dump because this is stored in NVRAM which is part of the dumped region.
NVRAM you can edit/extract/replace with UEFITool, it's usually the first volume (or two) in the BIOS region, and there is also a stock copy within the main volume that holds the setup module too.
However, I've not yet been able to compare a backlight off to a backlight on dump, so I cannot for sure tell you inside which submodule this setting is stored inside NVRAM.
If you get it working, please send me new dump to unlock, and I will compare that with dump you attached above with backlight disabled, then I'll know and be able to better advise others in the future!

I will wait to do the BIOS unlock, in case you get the backlight working,

@fv1862 may be correct with above AUFWINGUI method, I am not sure, you'll have to try and see. But, I do think for that method to work the backlight would need to be already enabled in the source file used (Dump with it already enabled, or modified BIOS with it enabled etc)
You can try with stock source though, but I assume that may erase your serial, unless you use your dump BIOS as source and then we know the outcome since backlight is disabled already

@Lost_N_BIOS I tried to edit some of the NVRAM values with HxD (and replacing it with UEFITool), but I had no success. I didn't want to start typing random things on random locations just to be sure, but I wrote a 7C at an offset of DD from NVAR CNFG (which is what asus bios tools is supposed to do), but it gets resets to FF after a reboot (didn't test if it was there after flashing before restarting the computer). The same thing happens with other configuration which is supposed to save the keyboard backlight level (it was set at 01, modified it to FF but it was also reset).

NVRAM is visible, from UEFITool, on v53 alpha, but replaceable on 0.25 (stable).

I also wanted to make sure that I was writing at the correct offset, but I have no way of comparing, as I only saw other people using this utility to rewrite MAC addresses after an improperly backed-up bios and this notebook doesn't have an ethernet port.

Regarding the AFUWIN method, I am unable to test it as not one BIOS file I could find for this machine had this non-critical block present (n2).

Just FYI, this laptop doesn't come with a backlit keyboard, but the more premium model S510 does, and it's exactly the same machine (same motherboard, same everything, except for the one having a discrete GPU). In fact, my laptop has the keyboard's backlight connector.

@noreplyse - I'm not sure how familiar you are with this kind of editing? But you have to open the file in UEFITool, expand the NVRAM volumes, expand again, and then expand again past compression (4x on the inside BIOS volume one), then do that write after the header of first internal module, if it even goes into that module (?).
You can't just random extract and edit, you have to extract properly and then edit at proper location (not including header in the count to reach "dd" - so body of whatever you edit), so yes, how you mentioned is probably not correct location. Inside NVRAM there is no NVAR CNFG, "Setup" config is the first entry module
And there is usually two NVRAM volumes at top of BIOS region, and one sub-volume inside main BIOS volume too, that's why I'm unsure proper location without having broken and working dumps to compare.

In stock 309 BIOS, on inner NVRAM volume inside main BIOS volume DD = 00 and is five bytes after a 69 (Same for main NVRAM volume at the top). So, if this is where you made the edit, then this is not the correct module apparently.

In your search for an answer on this, did you ever come across someone's dumped BIOS with this broken and then someone gave back to them edited and fixed, or provided them a fixed proven working dump? If yes, see if you can find that again and grab both BIOS for me.

@Lost_N_BIOS

I'm sorry I didn't reply earlier, but I was away for a few days and had no internet access.

What I did was the following: locate CNFG entry inside NVRAM in my dumped bios, extracted body, edited with HxD at offset DD (this is not counting header, as it already was clipped out), and inserted in the original dump with UEFITool.

This NVAR entry is not included in stock bios (I don't know why), so you won't find it in stock 309 (ps: I'm using v308, as v309 has stability problems)

I am editing the entry showing in the picture attached in this post.

Thank you for your time, really.

Update: I flashed a stock v308 to reset all the NVRAM variables (which they were according to UEFITool), the CNFG module didn't appear and the bt utility didn't work (it gave the same error message as before).

In the meanwhile, I'm searching and asking for a ASUS S510 bios dump, as those are the same laptops but with the backlit keyboard enabled.

Stock BIOS wont contain many necessary things inside NVRAM, so that is not a good thing to do you mentioned, it's not resetting NVRAM but erasing important data (Settings, board specific details like serial, MAC ID etc).
I suggest you reprogram/flash your original BIOS with fully populated NVRAM volume, also, often actual onboard BIOS contains two NVRAM volumes at the top (Stock never does)
Did you check your BIOS (not stock one downloaded, or one that has been programmed or FPT'd with stock region, but actual dump from board before anything is done), for second NVRAM volume at top? Check there and see if CNFG entry too.
Is your BIOS dump in post #12, a dump before you did anything BIOS related at all? If not, can you please send me your first original backup before doing anything BIOS related.

On your CNFG body edit, this change was from FF to DD right before byte that is "06" and 8 bytes after a "F8" correct? if yes, then that looks like proper location to me


If you extracted entire NVRAM volume (Body), that only removes the main header, each entry also has it's own header too that you'd need to count past in your edit (With header in place DD location = ED)


I have dumps from users of the following, and could get others probably, but I need to know full exact model you are looking for
ASUS VivoBook S15 S510UNR
Asus VivoBook S15 S510UF-X510UF AS301

@Lost_N_BIOS

The vanilla bios dump (unmodified one) is attached in this post. The one on post #12 was not edited, but was dumped after trying to use the bt app, so it may have messed with some NVAR entries.

Although this dump also has the CNFG entry, I can't seem to find another NVRAM volume.

I changed the value from FF to 7C exactly were you mentioned: before that byte that is 06.

I don't know exactly which model has a backlit keyboard enabled. Both are supposed to come with this type of keyboard (in reality, all S15/S510 should have a backlit keyboard).

Thanks

EDIT: Dumped the bios after editing the mentioned value and it was reset to FF. Probably there is a configuration elsewhere that is replacing it? I really don't know that much in order to establish this

It's normal, some BIOS (less often than usual) contain only one NVRAM volume at top (There is always a stock one inside main BIOS volume too, but this contains only stock entries and no CNFG nor many of the other usual entries)

So you changed the one I circled, before 06? If yes, that is correct one. How did you then flash that BIOS in? If AFU, what /switches did you add or what boxes did you check if GUI? If FPT or programmer, it should have locked in as programmed.
How you flash/program this in is going to determine if it sticks or not.

I checked the user dump I have from S15 S510UF-X510UF AS301 (The other ASUS VivoBook S15 S510UNR, does not have CNFG.)
The S510UF-X510UF one has FF before 06 there to in it's CNFG, it's user @Leeonard - maybe he can tell us if he has working backlight on his keyboard or not.
I noticed his CNFG has a lot more data, several lines populated at top (00-30)

I flashed the bios using FPT (with rewrite option). Doing a dump after flashing reveals that this setting is being modified, but then, after a reboot, it goes back to the original value (FF).

If that S15 doesn't have that 7C instead of FF, I really don't know anymore. Maybe this setting is being stored elsewhere in the NVRAM? Because I see no reason for the asus bios utility to work (bt). Also, if this is the case, this is relatively new, as people with ASUS laptops with Hasswell processors do use this utility to enable the backlight.

I will contact asus technical support and see if they can lend a hand on the matter, as I understand that the process for enabling the backlight with bt utility also came from them.

Regarding the unlocking of the bios posted by fv1872 on post #10, did you have time to take a look into it? I mean, I could really try it myself, I have no trouble editing with HxD and all that, the issue is that I didn't quite understand the process hehe :)

I really appreciate all your time spent on this topic, thanks.

@noreplyse - But, you said BT tool didn't work for you either. Maybe your replacement board does not have the correct traces or resistors to enable this? Hopefully @Leeonard will reply and let us know if he has working backlit keyboard or not, if not then we know that's not a good BIOS to compare with.
On all the threads you seen discussing the BT tool, did anyone post a "Working BIOS with backlight enabled"? If yes, try to find again and download that one so we can compare, can be any model, then we'll see if CNFG in NVRAM is correct or not.

You're welcome, and yes, I can unlock this BIOS, sorry I forgot you wanted and have been getting behind lately! Which BIOS here do you want me to use? I didn't look back, and probably already have your backup, just unsure which one to use, but it needs to be a FPT BIOS Region backup.

@Lost_N_BIOS

I doubt there is a change in the circuit, or that the components necessary are not soldered on, specially as it would make no sense to solder only the connector and none of the components necessary to drive the backlight.

There are some bios dumps with working keyboard backlight, but all of them are of older computers and most are enabled using the BT utility, which is why I now doubt if the setting controlling the backlight is the same, as it would have worked for me. I will leave attached a dump I found which is suppose to have working backlit keyboard, but this one doesn't seem to have the CNFG entry. If you want, I can upload more dumps if you think they are of any use.

Don't worry about it! There is no rush. You can use the dump on post #24, which is the original dumo with v308 made with FPT.

Hello!, i am sorry to say, but I have no phisical backlit keyboard, so I don't know if this is enabled or not in BIOS/NVRAM

@noreplyse - It may have been cheaper for them to leave the connector attached (Added) in some models and still yet not add other stuff, due to how production runs are made, you can't be sure.
But yes, I do agree in general with your thoughts, one would think if they didn't take them out of the assembly line before the connector is added why would that later before smaller items added in.

Thanks for dump, but we need one at least with CNFG in it, if we're still thinking that's the control/saved location. Do you know if they G74 users were using the BT Config utility, with success or not? If yes, and it worked to correct, then this is not stored in CNFG, at least not the one we've been looking at.
I'll check that dump

And thanks, I'll use BIOS #24 to unlock a BIOS for you

* Edit - I was inspecting bt.exe and I see it can also write to MNFG, test writing 7C to DD there and see what happens? And I can now confirm this is stored in BIOS only, not some other chip, this exe is for writing back to BIOS rom only.
I say this because on some BT discussion threads before I saw a few people trying to convince someone this isn't stored in the BIOS (it is)

I also just remembered, I have a G74SW and C90S here, I can test and see if I can figure anything out with those! Both have backlit keyboards I believe

Thanks @Leeonard - I'll stop tagging you now, last one to tell you thanks for stopping back in to answer