Forum Discussion
My Laptop works with one charger but not another identical charger
My laptop charges without any issues when using one specific charger, but it fails to charge at all with another charger that appears to be identical in model and specifications. Both chargers have the same output voltage and amperage and fit the same port, yet the second one does not work. I have tried swapping cables and testing both chargers on different outlets. The working charger powers the laptop every time, while the other shows no charging indicator and the battery level continues to drop despite being plugged in. I am looking for advice on how to diagnose this issue further, troubleshoot possible causes, or if this suggests a problem with the charger itself or the laptop's charging circuitry.
2 Replies
Because one charger works reliably with the same laptop, the laptop’s battery and charging circuit are probably fine. The second charger is more likely defective, incompatible internally, or failing the charger-identification process.
Matching voltage and amperage on the label is not always enough. USB-C chargers must provide the correct Power Delivery profile and complete electronic negotiation with the laptop. Barrel-type chargers may use an identification pin or chip; if that contact is damaged, the laptop may reject the charger even though the plug fits.
Try these checks:
- Shut down the laptop completely and connect each charger separately. If only the known-good charger activates the charging light while Windows is not running, this is not a Windows 11 problem.
- Compare the full model and part numbers, total wattage, output profiles and connector polarity, not only the maximum voltage and amperage.
- Inspect the suspect charger, connector and identification pin for looseness, bent contacts, heat damage or discoloration. Stop using it if it becomes unusually hot, smells burnt or makes noise.
- Enter BIOS/UEFI with each charger connected. Some laptops display the detected adapter type and wattage. If the second charger appears as Unknown, None or the wrong wattage, its identification or power negotiation is failing.
- For USB-C charging, test with a cable rated for the laptop’s required wattage and use the USB-C port that supports charging. A cable that works for data or phone charging may not support full laptop power.
- If possible, test the suspect charger on another device confirmed to support the same charger specification.
If the second charger fails these tests while the first continues working, replace it or make a warranty claim. Do not open the power adapter or attempt an internal repair, because it contains hazardous mains-voltage components.
Crucially, this issue does not indicate a widespread problem with your laptop's charging circuitry. Because the laptop charges perfectly with the known-good charger, the main power path on the motherboard is almost certainly intact. A problem with the laptop's charging circuit would likely affect all chargers, not just one specific unit.
