Repair Success Dell XPS M140

I'm always a sucker for a bargain, sometimes going way out on a limb only to watch it be chopped off.

Picked up the above today fairly cheap off Craigslist. Symptom was that battery wasn't charging, and backlight intermittent (it almost never worked).

Battery issue turned out to be due to aftermarket power supply. Fixed.

Symptom: backlight came on upon power up, but only lasted a few seconds. Would again come on after return from hibernate mode. External display worked fine. Visible image on the internal LCD.

Web research indicated this model had an issue with display, most often due to a defective magnetic reed switch which signals lid closure. Diagnostic test for this is to put a small magnet near the location of the switch and observe. I did that, except I used a hard drive magnet. Sure enough, the screen lit momentarily, and the machine went into standby...as if the lid was being closed.

Further experimentation produced longer 'on' times, so I thought I might be 'on' to something. Sure enough, exercising the reed switch repeatedly with the powerful hd magnet apparently 'unstuck' the switch, and it's working fine now.

I wonder if it will last....

jak

Reply to
jakdedert
Loading thread data ...

t

Reed switches are problematic at best. I worked at Bell Labs for many years, one of our switching systems used reed relays as the actual switches in the voice path. It was as much an art as a science to produce reed switches that would hold up for the projected lifetime of

40 years of use. so, keep that magnet handy, you may have to use it again.
Reply to
hrhofmann

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.