Dell Inspiron 640M E1405 Touchpad Issue
OK, it's not THAT difficult to replace the mouse button. I didn't have the ambition to follow Frumper's suggestion of replacing the little rubber dome with a spring, but there are a number of these available on ebay for under $30. If you're lucky, you'll find the whole top plate with the touchpad and mouse buttons - that saves a little time. But the disassembly/reassembly isn't too bad - there's a pdf of the disassembly process out on the web somewhere; if a google doesn't find it I can send it along. Basically, there are a LOT of little steps, and of course, everything is tiny and fragile. But what it entails is removing all the screws from the bottom of the machine - except for the two under the battery, they're identical. Don't forget the ones under the modem and CPU covers. Remove the 4 screws holding down the heatsink to the cpu. Pop out the hard drive. On the top side, pry off the plate with the power button, GENTLY remove the LCD plug and the 2 backlight connections. Then you can remove the 4 screws that hold the LCD assembly in place - put it somewhere safe! The keyboard will pop right up - be careful with the keyboard connection, the connector hinges, whereas most of the others have a locking key. With the keyboard out of the way, there are a final 4 screws holding the palmrest in place. When they're removed, disconnect the ribbon wires and just pry gently around the edge - starting at the back - and the whole palmrest will come off. If you've got a new palmrest assembly, you're ready to reassemble. If you've just got the mouse buttons, you'll have to remove the (4?) screws holding the front subframe to the palmrest, and a couple more ribbon connectors. Be VERY gentle with all the ribbon wires, and it goes back together very simply. I've done this a few times now; the first one took about 2 hours as I tried real hard not to break anything. Now they go in well under an hour. Like Frumpy said, not for the faint of heart, but not exactly rocket science either. Good luck!