this laptop works fine except that once it is shutdown, it will not power back up unless the battery and charger have both been disconnected first. then it will automatically power up just like it should. basically the power button will wake it from a sleep but it will not power it up from a shutdown. all power sources have to be detached first in order for it to power up
-
I am looking at an A2337 and found this for the order of power rails and what they do. Can this be confirmed before I dive into hunting down power rails that do not exist or are not neccisary?
- PPBUS_G3H (12.6V-12.8V)
- This is the main power rail that supplies power to the entire system. Check this rail first, as it must be present for other power rails to work.
- PP3V42_G3H (3.42V)
- This power rail is derived from PPBUS_G3H and is used to power the SMC (System Management Controller) and other essential circuits. It should be present if PPBUS_G3H is working correctly.
- PPVRTC_G3H (3.3V)
- This
- PPBUS_G3H (12.6V-12.8V)
-
Hello,
With the power button connected it either boot loops with the apple logo or no display but the charging meter shows it looping on charging every few seconds.
No corrosion any where!
Tried a replacement power button off ebay and the same.
Very occasionally it will work with the power button connected!
Same results with or without the battery.
Can it be a fault with the Audio board or the mainboard?
The touch Id assembly connects through the Audio board first then to the Mainboard.
Flex... -
Hi.
Long shot but does anyone have a schematic & boardview for the audio board+power button on a Macbook A2179?
There is a shorted cap on mine and I need to know if I can safely remove it or whether I need to replace it and with what capacitor.
Many thanks. ...08-21-2025, 02:38 PM -
- forum postHP 14-bf054sa
LA-F301P Rev 1.0
This laptop came in with a number of minor issues (Screen with black bar and battery that needs replacing). The laptop also had issues relating to salt (water/air) corrosion, having been used near the ocean.
The HDMI port, 2x usb ports and the SD card reader all needed replacement as they had been affected by salty air and only work intermittently. The HDMI port, 2x usb ports and the SD card reader have been replaced and have been checked for (obvious) shorts.
The laptop now fails to turn on (normally).... -
Dell laptop (E7440, uses the notorious CD3301B power controller + MEC5075 EC + BQ24715 charger IC)
Symptoms:- Laptop works normally on a pre-charged battery.
- Battery does not charge when adapter is connected.
- Without battery:
- Laptop powers on from DC adapter, passes CPU/RAM init checks, then cuts DC power abruptly.(seems to shutdown one of the mosfets in the charger path). Then the loop continues indefinitely
- Speakers “pop” when power cut occurs indicating harsh sutdown.
- If RAM is removed, the system shows RAM missing blink error code indefinitely without cutting DC power
Comment