Laptop typing 7 non-stop??

ButchB

n00b
Joined
Mar 12, 2009
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I have a laptop that as soon as you left click the touchpad to type it just starts sending 7 across the field. I have removed the keyboard and it still does it. So I ruled out stickey key. Plugged in USB motherboard and same problem.

Any ideas??
Thanks,
Butch
 
Sounds like it could be a bit of contamination between some of the pins on the keyboard controller on the motherboard, worst case it could be the motherboard going bad or you could be developing cracked solder joints on the chipset BGA, which requires either reflowing the BGA or replacing the mobo. how old is the laptop, whats the make and model?
 
Could be:

motherboard
keyboard
touchpad
top case

hope you're under warranty and it's not physically damaged
 
A very old Compaq Presario 2104US.

Its not worth it to put to much money into it but some time costs me nothing.
All else fails maybe I'll stick the MB in the oven and try to reflow the joints myself.

All the parts on the web are used. So I'd be taking some chances there.

Thanks for the replies!
Butch
 
I did some looking on your particular laptop, it appears to be a known issue with Compaq laptops, the keyboard was designed by Foxconn. Apparently it is a heat issue, http://www.karlin.mff.cuni.cz/~motl/hp-keyboard/compaq-keyboard.html many of the used keyboards out there will suffer the same problem. Some people have used an external keyboard like you were attempting to. The key is to remove the old keyboard, disconnecting the ribbon cable connecting the keyboard to the motherboard, and then the external keyboard would work properly. The downside of course is that it is no longer easily portable. So this was only done if the laptop was going to remain stationary. If you can find a new/unused keyboard for a good price it might be worth it. But expect the same problem to rear its ugly head again in the future at some point. Hope this helps.
 
Here is where I am.

Laptop keybord and touch pad removed.
USB mouse and keyboard plugged in.
Trying to load xp after Killdisking the HD.
When it comes time to click on box and type in anything thats where the trouble starts.

Types continous 777777777777777 automatic without touching any keys.
I can hold any key down and it will alternate between the two. For example 7878787878.
Why 7????

So what do you think. Its old but it would be a great laptop for a kid heading to college. Everything else was working perfect.

Thanks for helping!
Butch
 
Hmm, at this point it could be an issue with the keyboard controller (I hope I got taht right) or whatever part on a laptop that interprets the keyboard. Which means a whole new laptop motherboard.

So that means you're better off with a new laptop since laptop mobos costs quite a bit cash.
 
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