ThinkPad T400 blinking battery and charger leds on charger. - YouTube
Solved] Lenovo Plugged In Not Charging - Driver Easy
Thinkpad T400 Libreboot 160GB SSD 2.26GHz w/ 8GB RAM 9-Cell Bat AC ThinkLight | eBay
Lenovo charging light is white and pc won't turn on : r/Lenovo
T480 charging issue. Red light is showing but laptop is not charging. Sometimes it gets opened and gives error message- "The connected AC adapter has a lower wattage than the recommended model
Lenovo Thinkpad T400 with ArcaOS 5.0
ThinkPad T400 blinking battery and charger leds on charger. - YouTube
SOLVED: Power / Startup Issue? - ThinkPad T420 - iFixit