My HP 15-FC-1004AU laptop has developed several problems that may be related. It has an AMD Ryzen 5 7000-series processor, integrated Radeon graphics, 8 GB of DDR5 memory, a 512 GB SSD, and Windows 11.
It would occasionally freeze with a completely black screen while either idle or in use. The power light and sometimes the keyboard backlight stayed on, but the mouse, touchpad, keyboard, Caps Lock indicator, display reset shortcut, and lid close/open action had no effect. The only way to recover was holding the power button for about 10–15 seconds, which made it seem like the entire system had locked up rather than just losing video output.
After some of these unexpected shutdowns, the laptop displayed an HP 90B fan error. The fan appears to spin, and both HP's Fan Speed Test and Fan Thermal Test passed. The warning usually appeared immediately after an unexpected shutdown and disappeared after the laptop had cooled down completely.
The most serious failure happened while I was playing a video with around 13 browser tabs open. After roughly 16–17 minutes, the laptop suddenly switched off and has not powered on since. Holding the power button for about 15 seconds did not help, and connecting the barrel-style charger produces no charging LED or any other visible response.
Could the freezes, fan warnings, and complete no-power condition be connected? Possible causes I am considering include a failed charger, battery or charging circuit, motherboard power fault, thermal protection, an intermittent fan RPM sensor, BIOS or firmware trouble, or a memory problem. What safe checks should I try first, such as testing with a known-good charger or disconnecting the battery, and when should I stop troubleshooting and take it to a repair technician?
3 Answers
The first thing to rule out is the charger. A failed barrel-style HP adapter can result in no charging light and make the laptop appear completely dead, so testing with a known-good compatible charger is the safest and simplest next step. If another charger produces no LED or response, the fault is more likely somewhere in the laptop's charging circuit, battery connection, or motherboard.
If a known-good charger does not help, a technician would normally perform a power reset and then test the system in a minimum configuration. That can involve disconnecting the internal battery, removing external accessories and wireless hardware, and checking whether the board shows any LEDs or other signs of life when powered only by the adapter. Components can then be reconnected one at a time. Since opening the laptop and disconnecting the battery is unfamiliar to you, it is reasonable to have a repair shop do this rather than risk damaging a connector or shorting the board.
The previous freezes and fan errors make a motherboard or thermal fault more concerning than an ordinary Windows problem, especially now that there is no charging light. I would avoid repeatedly forcing it on and would prioritize testing the adapter and having the power circuit inspected.
A 90B warning does not always mean the fan is completely stopped. Laptop fans report their speed through a tachometer signal, and an intermittent sensor, slow startup, obstruction, poor heat transfer, or thermal problem can trigger the warning even if the fan passes a diagnostic test later. The fact that it appears after an unexpected shutdown and clears after cooling suggests an intermittent fan or temperature-related fault is possible. The fan, heatsink, exhaust path, and thermal compound should be checked by someone comfortable servicing laptops.
That makes sense. I don't currently have another compatible charger, so I haven't been able to eliminate the adapter as the cause. Since there is no charging indicator at all, I will try to test with a known-good one before opening the laptop further.