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Ctrl, num lock... light indicators not working correctly
Ctrl, num lock... light indicators not working correctly
Today I noticed on my Thinkpad L590 that the light indicators don't turn on/off correctly on caps lock, numlock, etc. Usually when I click the button, the light doesn't turn on (the button works anyway). Sometimes they turn on by themselves and start blinking (turning on and off). Sometimes three of them start blinking at the same time (capslock, numlock and F4 for mic). I don't know what's going on, the lights seem to work on their own, backlit works correctly. is updated, also updated from Vantage. I tried reinstalling keyboard drivers, but it didn't fix it, safe boot also doesn't help.
Re: Ctrl, num lock... light indicators not working correctly
Welcome to the forum.
A short in the keyboard circuitry responsible for LEDs? The laptop should be in warranty; I would request a keyboard replacement.

A short in the keyboard circuitry responsible for LEDs? The laptop should be in warranty; I would request a keyboard replacement.
Thinkpad 25 (20K7), T490 (20N3), Yoga 14 (20FY), T430s (IPS FHD + Classic Keyboard), X220 4291-4BG
X61 7673-V2V, T60 2007-QPG, T42 2373-F7G, X32 (IPS Screen), A31p w/ Ultrabay Numpad, A21m 2628-GXU
X61 7673-V2V, T60 2007-QPG, T42 2373-F7G, X32 (IPS Screen), A31p w/ Ultrabay Numpad, A21m 2628-GXU
Re: Ctrl, num lock... light indicators not working correctly
It could be bad contacts in the keyboard connector such that the power rail for the LED's are intermittent? I've had that in quite a few older Dell laptops because the LEDs on those are either on the keyboard like this one, or on a daughter board and the connection go bad.
Dell Lat CP MMX-233 64mb 40gb W2k
600 PII-266 416mb 40gb WXP
T23 PIII 1.13ghz 1gb W7
Precision M4300 X9000 8gb 160gb WUXGA Ultrasharp fp W10
T530i 15.6" i7 16gb fp W10
UXGA:
A30p PIII 1.2 1gb W7 (IDTech)
T43p 2.26 2gb fp W10 (Sharp)
Lat C840 P4-2.5 2gb 60gb W7 (Ultrasharp)
600 PII-266 416mb 40gb WXP
T23 PIII 1.13ghz 1gb W7
Precision M4300 X9000 8gb 160gb WUXGA Ultrasharp fp W10
T530i 15.6" i7 16gb fp W10
UXGA:
A30p PIII 1.2 1gb W7 (IDTech)
T43p 2.26 2gb fp W10 (Sharp)
Lat C840 P4-2.5 2gb 60gb W7 (Ultrasharp)
Re: Ctrl, num lock... light indicators not working correctly
So it seems the problem is probably with keyboard's contacts. Is there a way to display which key is active (caps lock for example) on display?
Re: Ctrl, num lock... light indicators not working correctly
The older Windows 7 based hotkey utility have this feature because the T410/T510 and later removed the num lock led. I don't think that utility supports such new thinkpads.
Dell Lat CP MMX-233 64mb 40gb W2k
600 PII-266 416mb 40gb WXP
T23 PIII 1.13ghz 1gb W7
Precision M4300 X9000 8gb 160gb WUXGA Ultrasharp fp W10
T530i 15.6" i7 16gb fp W10
UXGA:
A30p PIII 1.2 1gb W7 (IDTech)
T43p 2.26 2gb fp W10 (Sharp)
Lat C840 P4-2.5 2gb 60gb W7 (Ultrasharp)
600 PII-266 416mb 40gb WXP
T23 PIII 1.13ghz 1gb W7
Precision M4300 X9000 8gb 160gb WUXGA Ultrasharp fp W10
T530i 15.6" i7 16gb fp W10
UXGA:
A30p PIII 1.2 1gb W7 (IDTech)
T43p 2.26 2gb fp W10 (Sharp)
Lat C840 P4-2.5 2gb 60gb W7 (Ultrasharp)
Re: Ctrl, num lock... light indicators not working correctly
If the keyboard was replaced, would that fix the issue? I'll probably keep it for now, because I don't really look at keyboard much anyway.
Re: Ctrl, num lock... light indicators not working correctly
My guess is that most likely even if you reseat the cable after cleaning the connector with contact cleaner, the LEDs will start to work again. Whether that voids the warranty I have no idea.
Dell Lat CP MMX-233 64mb 40gb W2k
600 PII-266 416mb 40gb WXP
T23 PIII 1.13ghz 1gb W7
Precision M4300 X9000 8gb 160gb WUXGA Ultrasharp fp W10
T530i 15.6" i7 16gb fp W10
UXGA:
A30p PIII 1.2 1gb W7 (IDTech)
T43p 2.26 2gb fp W10 (Sharp)
Lat C840 P4-2.5 2gb 60gb W7 (Ultrasharp)
600 PII-266 416mb 40gb WXP
T23 PIII 1.13ghz 1gb W7
Precision M4300 X9000 8gb 160gb WUXGA Ultrasharp fp W10
T530i 15.6" i7 16gb fp W10
UXGA:
A30p PIII 1.2 1gb W7 (IDTech)
T43p 2.26 2gb fp W10 (Sharp)
Lat C840 P4-2.5 2gb 60gb W7 (Ultrasharp)
Re: Ctrl, num lock... light indicators not working correctly
Hi, sorry for late reply. So would it be better to send it to service or try to do something on my own with hardware?
Re: Ctrl, num lock... light indicators not working correctly
See on the screw holes whether there are warranty void stickers and things like that.
If there are none, maybe you can try to take off the keyboard but be very careful about how much torque you apply to the screws so they don't look worn. Be also careful about leaving fingerprint marks inside the keyboard.
Fortunately most ThinkPads prioritise keyboard replacement so it shouldn't be too hard.
Dell Lat CP MMX-233 64mb 40gb W2k
600 PII-266 416mb 40gb WXP
T23 PIII 1.13ghz 1gb W7
Precision M4300 X9000 8gb 160gb WUXGA Ultrasharp fp W10
T530i 15.6" i7 16gb fp W10
UXGA:
A30p PIII 1.2 1gb W7 (IDTech)
T43p 2.26 2gb fp W10 (Sharp)
Lat C840 P4-2.5 2gb 60gb W7 (Ultrasharp)
600 PII-266 416mb 40gb WXP
T23 PIII 1.13ghz 1gb W7
Precision M4300 X9000 8gb 160gb WUXGA Ultrasharp fp W10
T530i 15.6" i7 16gb fp W10
UXGA:
A30p PIII 1.2 1gb W7 (IDTech)
T43p 2.26 2gb fp W10 (Sharp)
Lat C840 P4-2.5 2gb 60gb W7 (Ultrasharp)
Re: Ctrl, num lock... light indicators not working correctly
I tried removing the keyboard, but I found out that I need a special keyboard removal tool so I could only remove the touchpad buttonskfzhu1229 wrote: ↑Tue Nov 17, 2020 10:56 amSee on the screw holes whether there are warranty void stickers and things like that.
If there are none, maybe you can try to take off the keyboard but be very careful about how much torque you apply to the screws so they don't look worn. Be also careful about leaving fingerprint marks inside the keyboard.
Fortunately most ThinkPads prioritise keyboard replacement so it shouldn't be too hard.

Also I think the lights worked before I updated the laptop, but I'm not 100% sure, I updated it rather quickly, including BIOS update. Recently I installed the newest BIOS, but it didn't help.
Re: Ctrl, num lock... light indicators not working correctly
Well the trackpoint buttons can be removed with a fingernail as well if you know what you are doing. I believe you can pry the buttons off from the bottom side and lift it up. There are 2 screws there, one on each side of the mouse buttons.MHD wrote: ↑Tue Nov 17, 2020 2:33 pmI tried removing the keyboard, but I found out that I need a special keyboard removal tool so I could only remove the touchpad buttons
Also I think the lights worked before I updated the laptop, but I'm not 100% sure, I updated it rather quickly, including BIOS update. Recently I installed the newest BIOS, but it didn't help.
But I do admit though that there is a tiny chance you might have broken clips on the buttons as a result. I guess it's your choice. Either live with the LEDs, send it back for warranty, or gamble and see if this helps.
Dell Lat CP MMX-233 64mb 40gb W2k
600 PII-266 416mb 40gb WXP
T23 PIII 1.13ghz 1gb W7
Precision M4300 X9000 8gb 160gb WUXGA Ultrasharp fp W10
T530i 15.6" i7 16gb fp W10
UXGA:
A30p PIII 1.2 1gb W7 (IDTech)
T43p 2.26 2gb fp W10 (Sharp)
Lat C840 P4-2.5 2gb 60gb W7 (Ultrasharp)
600 PII-266 416mb 40gb WXP
T23 PIII 1.13ghz 1gb W7
Precision M4300 X9000 8gb 160gb WUXGA Ultrasharp fp W10
T530i 15.6" i7 16gb fp W10
UXGA:
A30p PIII 1.2 1gb W7 (IDTech)
T43p 2.26 2gb fp W10 (Sharp)
Lat C840 P4-2.5 2gb 60gb W7 (Ultrasharp)
Re: Ctrl, num lock... light indicators not working correctly
Yes I was able to take off those 2 buttons and unscrew the 2 screws. But I couldn't get the keyboard off and I'm not sure if it can be done without the tool sadly.kfzhu1229 wrote: ↑Tue Nov 17, 2020 3:05 pmWell the trackpoint buttons can be removed with a fingernail as well if you know what you are doing. I believe you can pry the buttons off from the bottom side and lift it up. There are 2 screws there, one on each side of the mouse buttons.
But I do admit though that there is a tiny chance you might have broken clips on the buttons as a result. I guess it's your choice. Either live with the LEDs, send it back for warranty, or gamble and see if this helps.

Re: Ctrl, num lock... light indicators not working correctly
Well I am sure a plastic spudger should be able to do just that. If not, a small flat head screwdriver certainly will but you need to be careful with that one.
Also, just so you know, there is a rule on this forum that you can only embed a photo up to SVGA resolution and the title must claim it has a picture. This is for ppl with slow connections and/or old hardware
You can just give the link to the photo instead by removing the [img] tags.
Maybe this video helps:
https://www.youtube.com/watch?v=nJ9lGwRK2yE
The E580, E590, L580, L590 have the same keyboards I believe.
Dell Lat CP MMX-233 64mb 40gb W2k
600 PII-266 416mb 40gb WXP
T23 PIII 1.13ghz 1gb W7
Precision M4300 X9000 8gb 160gb WUXGA Ultrasharp fp W10
T530i 15.6" i7 16gb fp W10
UXGA:
A30p PIII 1.2 1gb W7 (IDTech)
T43p 2.26 2gb fp W10 (Sharp)
Lat C840 P4-2.5 2gb 60gb W7 (Ultrasharp)
600 PII-266 416mb 40gb WXP
T23 PIII 1.13ghz 1gb W7
Precision M4300 X9000 8gb 160gb WUXGA Ultrasharp fp W10
T530i 15.6" i7 16gb fp W10
UXGA:
A30p PIII 1.2 1gb W7 (IDTech)
T43p 2.26 2gb fp W10 (Sharp)
Lat C840 P4-2.5 2gb 60gb W7 (Ultrasharp)
Re: Ctrl, num lock... light indicators not working correctly
I was able to remove get out the keyboard, but I couldn't disconnect the cable, I couldn't open the metal locks that held the cables like I saw in some videos and manual. Also when flipping the keyboard I saw there were holes in the plastic on the back which indicate that the keyboard was remoevd, I dont know if this voids my warranty? Well I guess the best bet is to take it to a local service, but I can't find much information if I lost my warranty because of that.kfzhu1229 wrote: ↑Tue Nov 17, 2020 4:45 pmWell I am sure a plastic spudger should be able to do just that. If not, a small flat head screwdriver certainly will but you need to be careful with that one.
Also, just so you know, there is a rule on this forum that you can only embed a photo up to SVGA resolution and the title must claim it has a picture. This is for ppl with slow connections and/or old hardware
You can just give the link to the photo instead by removing the [img] tags.
Maybe this video helps:
https://www.youtube.com/watch?v=nJ9lGwRK2yE
The E580, E590, L580, L590 have the same keyboards I believe.
Re: Ctrl, num lock... light indicators not working correctly
Metal locks? I assume those are plastic ZIF connectors. Lift the black portion upwards, and pull out the cable.
If you don't have contact cleaners (I believe it's called deoxit in the united states), use alcohol on the gold pins of the connectors on your keyboard to clean off the connection. Do not use alcohol anywhere else as this stuff can short out electronics briefly, which might be enough to do damage if there are still electricity passing thorugh.
If you don't have contact cleaners (I believe it's called deoxit in the united states), use alcohol on the gold pins of the connectors on your keyboard to clean off the connection. Do not use alcohol anywhere else as this stuff can short out electronics briefly, which might be enough to do damage if there are still electricity passing thorugh.
Dell Lat CP MMX-233 64mb 40gb W2k
600 PII-266 416mb 40gb WXP
T23 PIII 1.13ghz 1gb W7
Precision M4300 X9000 8gb 160gb WUXGA Ultrasharp fp W10
T530i 15.6" i7 16gb fp W10
UXGA:
A30p PIII 1.2 1gb W7 (IDTech)
T43p 2.26 2gb fp W10 (Sharp)
Lat C840 P4-2.5 2gb 60gb W7 (Ultrasharp)
600 PII-266 416mb 40gb WXP
T23 PIII 1.13ghz 1gb W7
Precision M4300 X9000 8gb 160gb WUXGA Ultrasharp fp W10
T530i 15.6" i7 16gb fp W10
UXGA:
A30p PIII 1.2 1gb W7 (IDTech)
T43p 2.26 2gb fp W10 (Sharp)
Lat C840 P4-2.5 2gb 60gb W7 (Ultrasharp)
Re: Ctrl, num lock... light indicators not working correctly
Here's a picture of the connectors: https://imgur.com/a/JHyMYeRkfzhu1229 wrote: ↑Tue Nov 17, 2020 8:12 pmMetal locks? I assume those are plastic ZIF connectors. Lift the black portion upwards, and pull out the cable.
If you don't have contact cleaners (I believe it's called deoxit in the united states), use alcohol on the gold pins of the connectors on your keyboard to clean off the connection. Do not use alcohol anywhere else as this stuff can short out electronics briefly, which might be enough to do damage if there are still electricity passing thorugh.
But I will probably wait until the corona gets better and take it to lenovo service before I break anything, I'm not very computer savvy especially with laptops as this is my first one.
Re: Ctrl, num lock... light indicators not working correctly
Yes that's the ZIF connector I am talking about. You need to lift the black lever UPWARD and then the cable comes free. do NOT pull on the cable if there is resistanceMHD wrote: ↑Wed Nov 18, 2020 7:11 amHere's a picture of the connectors: https://imgur.com/a/JHyMYeR
But I will probably wait until the corona gets better and take it to lenovo service before I break anything, I'm not very computer savvy especially with laptops as this is my first one.
Dell Lat CP MMX-233 64mb 40gb W2k
600 PII-266 416mb 40gb WXP
T23 PIII 1.13ghz 1gb W7
Precision M4300 X9000 8gb 160gb WUXGA Ultrasharp fp W10
T530i 15.6" i7 16gb fp W10
UXGA:
A30p PIII 1.2 1gb W7 (IDTech)
T43p 2.26 2gb fp W10 (Sharp)
Lat C840 P4-2.5 2gb 60gb W7 (Ultrasharp)
600 PII-266 416mb 40gb WXP
T23 PIII 1.13ghz 1gb W7
Precision M4300 X9000 8gb 160gb WUXGA Ultrasharp fp W10
T530i 15.6" i7 16gb fp W10
UXGA:
A30p PIII 1.2 1gb W7 (IDTech)
T43p 2.26 2gb fp W10 (Sharp)
Lat C840 P4-2.5 2gb 60gb W7 (Ultrasharp)
Re: Ctrl, num lock... light indicators not working correctly
I found something new today. Usually when I press ESC the lights light up for about a second. I found that the correct keys light up, for example if caps lock is off it won't turn on and so on. So when it "randomly" lights up it actually does on the correct keys which seems to suggest that keys don't get power most of the time, no idea why. At least now I know it's not that random, but I don't know if this narrows the problem as I'm not an expert on how these things work.
Re: Ctrl, num lock... light indicators not working correctly
I tried reonnecting the keyboard cables after cleaning them with microfiber cloth, but it didn't fix the issue, the LEDs still don't work most of the time.
Re: Ctrl, num lock... light indicators not working correctly
Maybe check the solder joints on the keyboard connector? These E/L series ThinkPads can sometimes skim on manufacturing reliability as I saw someone with a E580 that has the stress relief of the LCD connector completely non-soldered!
Dell Lat CP MMX-233 64mb 40gb W2k
600 PII-266 416mb 40gb WXP
T23 PIII 1.13ghz 1gb W7
Precision M4300 X9000 8gb 160gb WUXGA Ultrasharp fp W10
T530i 15.6" i7 16gb fp W10
UXGA:
A30p PIII 1.2 1gb W7 (IDTech)
T43p 2.26 2gb fp W10 (Sharp)
Lat C840 P4-2.5 2gb 60gb W7 (Ultrasharp)
600 PII-266 416mb 40gb WXP
T23 PIII 1.13ghz 1gb W7
Precision M4300 X9000 8gb 160gb WUXGA Ultrasharp fp W10
T530i 15.6" i7 16gb fp W10
UXGA:
A30p PIII 1.2 1gb W7 (IDTech)
T43p 2.26 2gb fp W10 (Sharp)
Lat C840 P4-2.5 2gb 60gb W7 (Ultrasharp)
Re: Ctrl, num lock... light indicators not working correctly
I don't think there is much I can do anymore, they'll probably have to replace the keyboard if I want it to work correctly unless there is an even deeper problem but I doubt because everything else seems to work including external keyboard and its lights.
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