After disassembling my Presario 2100 to resolder the DC jack, the computer no longer recognizes the touchpad, and the LEDs for 'on/standby' and 'battery charging' no longer work.
Strangely, the LED for hard-drive activity does work.
The touchpad ribbon cable is connected. I am 99.999% it is seated all the way because I triend re-inserting it many times.
External PS/2 mouse works just fine.
In the Control Panel > Mouse there is no choice for touchpad, only the PS/2 mouse (when it's attached).
*However* - in the Properties and other tabs, it says 'Synaptics TouchPad Properties Version 6.7.4' etc. and clicking on 'Settings' brings up the Synaptics window, which is what you would see when the touchpad was working. But instead of having all the advanced settings for touchpad features, it says 'Properties for Standard Mouse on PS/2 Port'.
There were never any problems or unusual behavior with the touchpad before.
I went into BIOS Setup and reset everything to the defaults.
What could be going on here? Could I have physically damaged anything? I have disassembled the laptop a couple times to clean out the fan and replace the keyboard, with no problems.
many thanks
system:
Compaq Presario 2100 AMD
XP
40Gb, 756 Mb RAM
3 or 4 years old
I had the same problem with my ASUS F3E. Solved it myself. I have recognized that the ribbon cable (AWM E118077 2896 80C VW-1) connecting Synaptics Touchpad and main board has been bent by myself when reassemble. It had caused three of the connectors disconnected ( i tested both ends with multi- tester.)
It is very difficult to find a spare cable (the same one) here in singapore.
So I got the duty myself to repair the cable.
Fortunately i had bent near the closer end to the main board. I removed the disconnected (about 1.5cm) part with a paper cutter. Rubbed 0.5 cm of the cut-end to bring up the copper-lead connectors (This has to be done extremely carefully - I also passed this second time).
There was an existing plastic pallette in the removed end. I glued the same under the newly rubbed end - so that the thickness of the end gets the same as original.
Fixed the connectors back making sure I do not bend it again badly.
Hurrrrrrrrrrrrrraaaaaaaaaaaaaaaih!. It works guys.
But you have to have really good vision and confidence when doing the rubbing part. Because it can also remove the required metal lines in the ribbon. Make sure you have a very sharp paper cutter knife first.
Give it a try or else contact me if you need help. I'm in Singapore.
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