I have a HP DV9000, AMD chip, Quantas MOBO AT-8 circuit. The battery will not charge I checked the motherboard charging circuit (outside its case, with battery removed) I get the following voltages across the two mosfets in the charging circuit. Please refer to page 34 of the circuit diagram. P channel Mosfet PQ1(SI 4425BDY-T1-E3) immediately downstream of the AC adapter looks good(19V each on source and drain and 5.2v on gate), but P channel mosfet PQ4 (SI 4425BDY-T1-E3) indicates 19V on the Source pins 1-3, no voltage on the drain pins 5-8 and 19V on the Gate pin 4. I believe the mosfet is good but somehow the gate voltage should be much less tha 19V for the mosfet to activate. I will appreciate if anyone can assist me in identifying the problem
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