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CMOS Battery?

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larrym

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Oct 29, 2012
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Hello all,

I was just given a laptop (Toshiba l505) it will not boot. press the power button, and the hhd light flashes for a second, fan comes on for a second, and that's it. When plugged in, it shows the charge light and power plugged in light. No other sign of life. The guy that gave it to me stated it did this before, but then came back on after a day. Could a dead CMOS battery cause this? It's soldered to the board and cost about 10 bucks to replace, but I don't want to bother if you think the issue could not be caused by this.

There wasn't anything spilled on it, just wouldn't turn on one day according to the guy. I tried removing the battery, holding power button down trick (even though this has never worked for me)..removed each component (RAM, HDD, Wireless card,battery) and tried to boot, but same result.

thanks,
Larry
 
Hi :)

Generally speaking, when the lights flash for only a second or so, its normally caused by NO charge in the battery... or the charger is NOT working properly...

Test the charger with a VOLTMETER first...

All the best Brett :)

 
Thanks for the replies,

The charger test fine at 19.5 volts and the laptop does show the charging light on when the charger is plugged in. I tried a few different charges just to be sure as well as a few different batteries for the laptop. The only thing I have not tested, which I am able to test, is the CMOS battery. So I am guessing it is the MOBO or the CMOS battery..but I am not sure if a dead CMOS battery could cause these symptoms?
 
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