COMPAQ CQ42 QUANTA AX1 DEAD

[mcplslg123]

M/B: QUANTA AX1
MODEL: COMPAQ CQ42
PROBLEM: DEAD

This mb came dead. No light on dc jack.
3v, 5v rails present
no short to ground anywhere.
sensing voltage at battery connector & power switch present

after much effort found that SIO kb3926QF D2 was faulty as pin no 90(DNBSWON#1) should have 3.3 volt but was giving only 1.45 volt. This signal originates from kbc.

Replaced kbc. Now ok

[samanthban]

This signal (DNBSWON#1)comes after pressing the power button.your lap is dead .please correct me if I'm wrong

[mcplslg123]

Dear Samanthban, This is what i do mean also. After pressing power switch DNBSWON SHOULD BE 3.3V BUT WAS GIVING 1.45V.Yeh laptop was dead.

[samanthban]

Thanks for replying some what you did is correct learnt one thing thanks .I used to go for S4/S5 command .