Friday, April 22, 2011

Gateway laptop M-Series - Shuts off immediately [M-6750]

This Gateway M- Series  6750 arrived with the following symptoms: 

Turns on, but shuts off after about 5 sec.  The lights would flash, then shut down. Counting seven (7) flashes before shutting off. Attempting a cold reset of the BIOS/CMOS it would not complete the reset, and continue to do the same thing. 

Because it would not write the CMOS, that shows me the first area to check.  Under close inspection of the board, I notice a coil is burnt, and the number is not visible/readable. [PL20]

The burnt coil had also burned the motherboard layer under itself and would require cleaning and insulating the second layer. This was done with a small piece of mylar tape that was placed under the coil before soldering it in place. This repair was a quick repair and not making a complete mask and copper pad for the exit contact of the coil. Works and sufficiently insulates the second layer of the groundplane.

MOSFET PQ54 was also replaced simply because the cost is negligible and would be easier to replace while the unit was open rather than to reassemble and possibly have to replace anyway. The FET was  a Fairchild FDS6900AS  which is a 30V Dual N-Channel PowerTrench® SyncFET™

After replacing the coil, I partially reassembled the laptop simply enough to get power and connect the screen.  (Image blurred while holding camera)  It Works!  Reassemble and test rest of peripherals, USB, Webcam, etc...

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I cannot repair laptops for you via the internet, I can only answer questions related to posts. This is because I have not had experience on every motherboard that is out there. Bear with me.

If you do need it repaired. Contact me for quote (US/CDN Only)

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