Can't get keyboards to work on laptop

[shamrin]

A customer came in with a laptop that had a spill on it. The computer appears to work and, in fact, the keyboard had worked for a while then stopped. This looked like a normal replace-the-keyboard-everyone-is-thrilled job. After replacing the keyboard however, it still did not work - exactly. I've found that if I hold a key down for a long time, the keypress will produce the correct letter and continuing to hold it will fire off a character about once a second or two. Plugging in an external USB keyboard gives the same result. The on-screen keyboard works fine.

This is a Windows problem because the keyboard works fine in BIOS and using a Linux Live disc. The computer had a few virus issues which I've cleaned up now (perhaps there is/was a keylogger hanging around somewhere?). Safe mode, normal mode, same problem. Everything looks reasonable in the device manager, no missing or broken devices. I've uninstalled the keyboard drivers and let them re-install.

The "feel" is like the machine is at 100% usage and just can't pay attention to the keyboard but that's not reflected in the task manager.

All ideas welcome.

 

[NYJimbo]

If you are certain that it functions FLAWLESSLY outside of the installed O/S then it would seem that's the issue. The only other thing I could imagine is some kind of weird interrupt from the keyboard/controller but then you would probably get a buffer full warning or something.

What specific software did you use to scan for viruses ? I would definitely add combofix, roguekiller and Emsisoft. The idea of a keylogger or something sounds possible but you need good tools to find them.

 

[shamrin]

If you are certain that it functions FLAWLESSLY outside of the installed O/S then it would seem that's the issue. The only other thing I could imagine is some kind of weird interrupt from the keyboard/controller but then you would probably get a buffer full warning or something.

What specific software did you use to scan for viruses ? I would definitely add combofix, roguekiller and Emsisoft. The idea of a keylogger or something sounds possible but you need good tools to find them.

Well, since you asked in ALL CAPS, I'll admit that the machine does seem to be running hot. I did not let it run long enough in Umbutu to know if it cools down there. Going back to my gut feel, it's like it's running something that's not reflected in task manager. I've been seeing quite a few MBR viruses that are hard to detect lately, maybe I'll try re-writing the boot record to see it that brings any joy.

I have thrown combofix and hitman at it along with MWB so far. I don't come across many keyloggers really but I would expect one of those would have turned up something.

 

[NYJimbo]

Well, since you asked in ALL CAPS, I'll admit that the machine does seem to be running hot.

Ok, I was kinda meaning if the keyboard was working flawlessly. Can you boot a Windows install disk or windows recovery disk to see if the keyboard acts weird in that?. Just want to be sure that its not some bizarre issue with the post-spill motherboard and something unique to the windows environment like how it handles the keyboard/superIO/whatever.

 

[shamrin]

Can you boot a Windows install disk or windows recovery disk to see if the keyboard acts weird in that?. Just want to be sure that its not some bizarre issue with the post-spill motherboard and something unique to the windows environment like how it handles the keyboard/superIO/whatever.

If I boot to the Windows Startup Repair and open a console window, the keyboard works just fine. It may very well be something bizarre though!

I'm also have noticed that recognition of USB devices is really slow. It took it at least a couple minutes to recognise my flash drive.

Here's another data point that looks hopefull. I tried completely disconnecting the new internal keyboard and attaching a bog-standard Dell USB keyboard. Same problems. But, if I look in Device Manager, the Dell keyboard causes Microsoft eHome MCIR 109 keyboard to turn up. I gather this is some kind of Infra-red device. Now I also see under Human Interface Devices a bunch of entries associated with ENE CIR Receiver.

I've about had it with using the on-screen keyboard so we are rapidly heading toward a Nuke & Pave here I think.

 

[ComputerRepairTech]

If its windows7 here is a zip file of various keyboard registry entries:
http://www.computerrepairtech.com/tools/keyboard7.zip

However I truly have no idea if that will help you with this issue as i've never heard of that one. If you disconnect the laptop keyboard does it still happen on usb keyboards?

 

[FremontPC]

Pull the battery and try it with just the power cord. Any change?

 

[shamrin]

If its windows7 here is a zip file of various keyboard registry entries:
http://www.computerrepairtech.com/tools/keyboard7.zip

However I truly have no idea if that will help you with this issue as i've never heard of that one. If you disconnect the laptop keyboard does it still happen on usb keyboards?

Oh, that might be interesting to try the registry entries. And I did try it without the built-in keyboard, same problem.

Pull the battery and try it with just the power cord. Any change?

Yes, I was running without the battery the whole time actually.

I would like to have solved this problem but it's open-ended and I needed to get it back to the customer so we did a N&P.