LA-C421P BQ24780S no ACDRV
Collapse
X
-
-
Re: LA-C421P BQ24780S no ACDRV
Just trawling my old laptop diagnosing posts and seen added posts since original board view request..i lost interest in the board after a couple of months of unsuccessful attempts.
one day i may dig out the L560 board and try the sw 1 top pins bridge only suggestion by rbvdon..
board won't be worth much even if fixed, but hey, sometimes its about the challenge.
smd Flea, thanks for comment regarding mosfet bypass, At the time I watching to many early you tube videos (Sorin) showing mosfet bridging as a solution.
I now understand the dangers of inducing a false start scenario.Comment
-
Comment
-
Re: LA-C421P BQ24780S no ACDRV
The LA-C422P has a similar layout. https://www.badcaps.net/forum/showthread.php?t=88885 .I read on one forum that SW1 was broken causing a problem.Tape it down,if the switch is working ok and check CMSRC and ACDRV again.Comment
Related Topics
Collapse
-
Hi, I'll start by saying that I'm not an expert and I've reached a point where I don't know what to try/do anymore...
Starting from the beginning: I opened this subwoofer for the first time with a very strong smell of burnt electrical components, I realize that on the amplifier board there is a hole between V+ OUT and GND about the size of a finger, the damaged components were the shorted mosfets, two damaged zener diodes and two capacitors. I bought everything, I fixed the hole by cutting the pcb and putting a piece of a perforated board.
I had no problems connecting mosfets and capacitors,...-
Channel: Troubleshooting Audio Equipment
08-27-2024, 12:46 PM -
-
Hi,
Finally got time to fix this board up.
At first it didn't give any POST codes. Turns out it was an unsupported Celeron D cpu. After dropping in an Celery 2.6gHz the CPU came out of reset with clock signal, but still no post codes. For a while it did work when I applied pressure to the ADP3168 chip, but on next reboot the MOSFETs started to burn. Then I left it as is for months.
Now I came back prepared. Replaced the bad MOSFETs and the ADPxx18k drivers. Now I don't get any MOSFETs blowing up issues anymore. But sadly, the Vcore is missing. The whole VRM isn't... -
by flerreHi!
Managed to get a Gainward Phantom GTX 980 in an auction for a bin with components.
No video out so I started fault finding and found a blown fuse for 3 mosfets. Started checking for shorts and found what I think is a short through all of those 3 mosfets; 0.1 ohms between "VIN" input and "VSWH" output. All mosfets in this gpu are the same ones (NCP5369) with integrated drivers and when I tried measuring the other ones through these ports they were somewhere in the kilo-ohms range.
So, could I safely assume all of these 3 mosfets are... -
by Thomas SmithHello everyone, I have an ASUS FX506LI laptop that does not turn on, and I need help diagnosing the issue. Here is what I have checked so far:
Initial Symptoms:- The laptop has no power at all (no LEDs, no fan spin).
- No 3.3V or 5V present on the board.
- The power button (NBSWON#) reacts but only changes from 0V to 0.5-0.11V.
- Charger input (FETs PKCH2BB)
- Drain: 20V, Source: 0V, Gate: 0V (FETs not switching).
- BQ24780S Charger IC:
- VCC and ACDET are present.
- ACN / ACP, ACDRV, BATDRV, LODRV, HIDRV, ACOK, SRN, SRP – all 0V.
- Shunt resistor has 10Ω to ground.
-
Hello everyone
I have been working on this laptop mentioned in the title, it initially had a shorted capacitor. After I replaced it, the thing started working again, but there is still another problem. The laptop was running off a charger, the battery was reporting 96% charge... but when I unplugged the charger, the laptop died. I've measured the battery voltage - 0V. I think it is locked. (Screenshot from batterymon, below).
I've ordered a new 3rd-party battery, but I think there's something wrong with it too - the laptop boots, but the battery isn't charging. Also,... - Loading...
- No more items.
Comment