LA-C501P No ACDRV??

[dspok]

Re: LA-C501P No ACDRV??

From the voltage on pin # 20 (VCC), the charger IC @ PUB01 is not being powered.

See attached.

Review the parts that have been highlighted.

The dual diode and series resistor must be present and working to allow for the raw ~19v to reach this charger IC to power up this logic board.

On a normal logic board, pin #20 should be ~19 volts. Confirm it and update this thread.

Start with the voltage check on each pin of PDB1 (dual diode). Pin #1 should be about the same as the adapter voltage.

My bad, I attached wrong schematic. Board in NM-B731. I couldn't find schematic but boardview attached.

[mon2]

Re: LA-C501P No ACDRV??

See attached. It is the same flow. Check the voltages at each of the arrow points.

[dspok]

Re: LA-C501P No ACDRV??

See attached. It is the same flow. Check the voltages at each of the arrow points.

Pin28 has 19v. PD302 and PR314 is too.

[3mar]

i've fixed the same problem by replacing those component , the small capacitor was shorted and the small mosfet risistance was almost zero

[reefcool]

i've fixed same problem by change source PR311 from N1 to VIN

[mon2]

Interesting that this worked and thanks for sharing but the bypass should not be necessary if the mated parts are working properly. That is, the original board should function with the original wiring diagram.

[fredyjbi]

Re: LA-C501P No ACDRV??



Pin28 has 19v. PD302 and PR314 is too.

do you have a 19v csmrc on pin 3?
Measure all voltages on the charging IC
- cmsr 19v
- vin 19v
- acdet 2.6v
- regn 6v