Troubleshooting: Blinking Power LED

Started by baffo32, March 20, 2022, 09:42:03 PM

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Does anybody have capacity to leave a reminder of where to find troubleshooting or repair tips for this laptop?

Presently I have an issue where, when I leave it plugged in, it will after some time suddenly power off and the battery light may flash red for some time until I hold the power button. On reboot, I don't find any logs preceding the event and the battery is at 100%. This only happens while the laptop is plugged in.

I'm thinking I should know the meaning of that blinking led somehow.


This worsened. The system stopped charging and emitted a burning smell, the bottom was quite hot near the power connection. The charger makes some audible quiet staticy noise when used.

I opened it and found the heat seems to be coming from the rectangular component between the labels "DC5" and "D1". The component is blackened.

I measured the voltage of the charger. It gives 5v in brief spurts, mostly dropping to 0v, when not powering the system. When attempting to charge the system, it's at around 2.8V.

I infer this could be fixed with a replacement mainboard and charger. Not sure what happened, to prevent it in the future.


I looked up this diode and I'm guessing it's a power shunt to handle voltage spikes within the range of 6V - 10V.

I have an RS-232 USB adapter plugged into the system, and often get strange garbage or terminal closure when the device on the other end is rebooted.

I'm guessing that there could be 12V power spikes coming in via the RS-232 adapter that are breaking the diode. Not sure. But I'm thinking if I unplug it for the duration of the spikes, that this would be what to plan to do next.


Measure the voltage between the grounds of the laptop power supply and the ground coming from the USB-RS232 adapter - like we showed here 10 years ago:
Technical support and documentation manager at Olimex


If more people have this issue then refer to as it's likely caused by the wear of the power connector, the solution is to get a new charger or replace the charging port which can be done by any local repair shop.  If they don't know what to do then let me know i try to make a documentation to make that easier.
* Community Lead Developer of TeresDevelopment
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