M1330 Windows 7 Home Premium 32 bit. 4GB RAM, Corsair XTi 240GB SSD, BIOS A14, Intel Core 2 Duo T9500 @ 2.6 Ghz. Nvidia 8400M GS integral GPU with Copper shim mod.
This started when I had to remove the original NK750 keyboard to replace the LED/LCD screen.
Initially, when I re-booted, the following keys were inoperative:
B, N, /, spacebar, rightALT, left arrow, down arrow, right arrow.
Later, when the different keyboards were tried, the following additional keys became inoperative:
Presently the entire bottom row of keys, z through m, ,./ spacebar, rightAlt, rightCtrl, left arrow, right arrow, down arrow, enter keys are not working. I am thinking that this is a hardware problem and the motherboard will need to be replaced to fix a bad connection where the keyboard ribbon mates with the fold down latch.
The following troubleshooting efforts have been tried but the laptop keyboard problem persists:
A new generic un-branded keyboard was purchased, but it produced the same dead key results as my original keyboard.
A new Dell JM629 Black keyboard was purchased, but it produced the same exact dead key results as my original NK750 and the generic un-branded keyboard.
An external USB keyboard functions normally.
On screen keyboard functions normally.
Ease of access center sticky keys, toggle keys, filter keys, shortcuts were verified as off/unchecked.
Keyboard test using the Dell Utilities disc verified that the keys in my above list are not working.
Device manager shows “This device is working properly.”
OS upgraded from Vista Home Premium 32 bit to Windows 7 Home Premium 32 bit.
Keyboard driver updated to 6.1.7601.17514, no change.
Uninstalling the keyboard and letting Windows reinstall the keyboard, no change.
So, 3 keyboards exhibit the same dead keys.
Looking at the keyboard ribbon attach point through an 8x magnifying glass, I see no obvious bent pins or foreign objects.
I think I have eliminated all software issues, so my problem is probably hardware related. Is there anything else to try before ordering a new motherboard?
Below are troubleshooting steps to try and resolve the issue.
Perform a hard reset and test the keyboard.
To perform a hard reset, follow these steps:
1. Perform a full shutdown on the computer. (Do not suspend or hibernate).
2. Remove all the external peripherals, if any, connected to the system.
a. For laptops: Remove the battery (if the battery is Customer removable unit CRU) and unplug the power cable from the system
b. For desktops: Disconnect the power cable from the back of the system.
3. After unplugging, press the Power button for 30 seconds to drain any residual power from the computer.
a. For laptops: Reinsert the battery and plug in the power cord. If the battery was not removed, then plug in only the power cord.
b. For desktops: Reconnect the power cable and any necessary peripherals (Mouse, Keyboard, Monitor)
4. Press the Power button to turn on the system and allow it to boot fully.
5. Test the Keyboard.
Toggle num lock key.
Press the num lock key on your notebook. In order to have the functionality of a 101 key keyboard on an 85 key laptop, the Num lock key activates the 10 key keypad functions that would normally reside on the right side of a standard keyboard. Simply press <Num lock> again to go back to normal operation.
Thanks for the response.
I have tried numerous hard resets. Actually, every time the integral keyboard is removed, I performed all of these actions. A hard reset was just done again, but the same keys are dead.
My Num Lock key toggles a small lock indicator light with a number 9 inside. This functions normally, but has no affect on the numerous dead keys.
3 integral keyboards tried, all have the same dead keys:
zxcvbnm,./ Spacebar, RAlt, RCntl, Enter, Left arrow, Right arrow, Down arrow.
This all started when I had to remove and reinstall the original keyboard. I am suspicious that one or more of the receptor pins is not connecting with the ribbon cable, where the keyboard ribbon mates to the motherboard.
I ordered a reconditioned Intel graphics type motherboard and companion heat sink fan. This fixed the keyboard problem with the numerous dead keys. The keyboard was not the problem.
The connection of the keyboard ribbon cable at the motherboard did not look bad, but it apparently was bad.