ThinkPad L15 Gen 4 AMD USB-C Not Charging Fix
The Lenovo ThinkPad L15 Gen 4 AMD supports USB-C Power Delivery charging but only through specific ports and with chargers that meet minimum wattage requirements. If USB-C charging does not work, follow these steps to identify and fix the cause.
Confirm the correct USB-C port and charger wattage Check first
The ThinkPad L15 Gen 4 AMD requires a USB-C charger with at least 65W Power Delivery to charge at full speed. A 45W charger will charge slowly or show as plugged in but not charging. Confirm you are using the Thunderbolt/USB4 port (marked with a lightning bolt) rather than a data-only USB-C port.
Use an active USB-C cable rated for Power Delivery
Replace the USB-C cable with one certified for USB Power Delivery (USB-C to USB-C, labeled with the PD logo or rated at 5A/100W). Passive or charge-only USB-C cables cannot negotiate the 65W or higher PD profile needed to charge the L15 Gen 4 AMD at rated speed.
Update the Thunderbolt and USB Power Delivery firmware
Run Lenovo System Update and install any available Thunderbolt firmware or USB Power Delivery controller updates. These firmware updates fix PD negotiation bugs that prevent third-party chargers from being accepted by the ThinkPad L15 Gen 4 AMD charging circuit.
Reset the BIOS battery settings
In Lenovo Vantage, go to Device → Power → Battery Settings. Ensure Battery Charge Threshold is not set to a value below the current battery level, which would prevent any charger from starting a charge cycle. Reset to Default if uncertain.
Update the BIOS
Install the latest BIOS for the ThinkPad L15 Gen 4 AMD via Lenovo System Update. BIOS updates include Power Delivery protocol fixes that expand compatibility with third-party 65W and 90W USB-C chargers, including gallium nitride (GaN) compact chargers.
Common questions
Can the ThinkPad L15 Gen 4 AMD charge via USB-C from a power bank?
Yes, with a power bank that supports USB PD at 65W or higher. Lower wattage banks will charge slowly or not at all during heavy use.
What wattage USB-C charger does Lenovo recommend for the L15 Gen 4?
Lenovo recommends 65W minimum for charging and 90W for charging while under load. The included barrel-jack charger is 65W.
Will USB-C charging damage the ThinkPad L15 battery?
No. USB-C PD charging follows the same battery management rules as the barrel-jack charger and is safe for long-term use.
How do I know if USB-C is actually delivering power to the battery?
Look for a charging indicator in the taskbar battery icon. Also check Lenovo Vantage Battery settings for current charge rate in watts.
Hafiz, Kuala Lumpur: “My ThinkPad L15 Gen 4 AMD would not charge via my 45W USB-C charger. Swapping to a 65W PD charger with a certified cable fixed the issue immediately — it just needed higher wattage.”
Frequently Asked Questions
Does the ThinkPad L15 Gen 4 AMD support USB-C charging on both USB-C ports?
The L15 Gen 4 AMD has two USB-C ports but only one supports full Power Delivery charging. The port with a Thunderbolt or USB4 symbol supports PD charging at 65W or higher. The other USB-C port may only support data and lower wattage charging. Check the label next to each port on the chassis.
Can I charge the ThinkPad L15 Gen 4 AMD with a 100W USB-C charger?
Yes. The charging circuit will negotiate the appropriate wattage (up to its supported maximum) regardless of how many watts the charger offers. A 100W charger connected to a laptop that only accepts 65W will deliver 65W — it will not overload the circuit.
Why does the ThinkPad L15 Gen 4 say plugged in but not charging?
This usually means the charger wattage is too low to overcome the current power draw of the system, or the battery charge threshold in Lenovo Vantage is set above the current battery level. Check both the charger wattage and Vantage Battery settings.
Is a GaN USB-C charger compatible with the ThinkPad L15 Gen 4 AMD?
Yes, provided it supports USB Power Delivery at 65W or higher with a 20V/3.25A profile. GaN chargers from reputable brands (Anker, Baseus, Ugreen) are fully compatible with the ThinkPad L15 Gen 4 AMD and are significantly smaller than the original barrel-jack adapter.
Ryan holds a Computer Science degree and has over 20 years of hands-on experience with PC hardware, software, and driver troubleshooting. He is the author behind softwaredriverdownload.com, where he helps everyday users fix driver issues quickly and accurately. Ryan has personally tested most of the fixes on this site across a range of Windows 10 and Windows 11 machines.
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