Quick answer
- Ensure the battery is warm enough to charge; lithium-ion batteries refuse to charge below ~32°F (0°C).
- Check the charger LED indicators for fault patterns to identify potential issues.
- Inspect the battery terminals for dirt or corrosion that could disrupt the connection.
- If the battery is swollen, punctured, or corroded, do not attempt to charge it; recycle it safely.
Symptoms
When a DeWalt battery won't charge, you may observe several symptoms:
- Charger LED Patterns: The LED on the DeWalt DCB115 charger will show a solid red light if the battery is charging, a solid green light when fully charged, or a blinking red light if there’s a fault. If the light is blinking red and yellow, it indicates a pack fault.
- No Response: The battery may not power the tool at all, or it may power it intermittently.
- Unusual Sounds: You might hear clicking or buzzing noises from the charger, indicating a problem with the battery or charger.
Quick checks
Before diving into deep troubleshooting, verify the following:
- Temperature: Ensure the battery is above 32°F (0°C). If it's cold, allow it to warm up to room temperature.
- Charger Compatibility: Confirm you are using a compatible charger, such as the DeWalt DCB115 or DCB118, which can charge 20V MAX and FLEXVOLT batteries.
- Battery Terminals: Inspect the battery terminals for dirt or corrosion that may prevent a proper connection.
- Charger Functionality: Test the charger with another battery to ensure the charger itself is functioning correctly.
- Battery Age: Consider the age and usage of the battery; lithium-ion batteries typically have a lifespan of 2-3 years depending on usage.
Step-by-step fix
- Remove the Battery: Always start by removing the battery from the charger and the tool to avoid any electrical hazards during troubleshooting.
- Inspect the Charger: Check the LED light on the DeWalt DCB115 charger. If it shows a solid red light, the charger is working. If it’s blinking red/yellow, there may be a fault with the battery.
- Clean the Terminals: Use a soft cloth or a brush to clean the battery terminals. Dirt or corrosion can disrupt the electrical connection, preventing charging.
- Warm the Battery: If the battery is cold, bring it to room temperature before attempting to charge it again. This allows the battery management system (BMS) to engage properly.
- Charge the Battery: Reinsert the battery into the charger and observe the LED indicators. If it shows a solid red light, it is charging. If it fails to charge, proceed to the next step.
- Test with Another Battery: If possible, test the charger with a different battery to confirm that the charger is functioning properly. If the second battery charges, the original battery may be defective.
If the battery still does not charge, consider replacing it.
View DeWalt 20V MAX XR 5.0Ah Battery (DCB205) on Amazon (paid link)
View DeWalt 20V MAX XR 5.0Ah Battery (DCB205) on Home Depot (paid link)
If it still isn't working
If the battery continues to fail to charge after following the steps above, consider the following options:
- Warranty Service: Check if the battery is still under warranty. DeWalt offers a three-year limited warranty on batteries. If eligible, contact DeWalt customer service for a replacement.
- Service Center: Visit an authorized DeWalt service center for further diagnosis and repair.
- Replacement: If the battery is out of warranty and cannot be repaired, purchasing a new battery may be the best option.
FAQ
Why is my DeWalt battery not charging?
There are several potential reasons, including cold temperatures, a faulty charger, dirty terminals, or a defective battery. Follow the troubleshooting steps to diagnose the issue.
What does a solid red light on my DeWalt charger mean?
A solid red light indicates that the battery is charging. If it remains red for an extended period, it could indicate an issue with the battery.
Can I use my DeWalt 20V MAX charger with a FLEXVOLT battery?
Yes, DeWalt 20V MAX chargers can charge FLEXVOLT batteries, as they share the same electrical platform.
What should I do if my battery is swollen?
Do not attempt to charge or use a swollen battery. Dispose of it safely at a recycling center, such as Home Depot or Lowe's.
How can I tell if my charger is working?
Test the charger with a different, known-good battery. If the charger charges that battery, it is functioning correctly. If not, the charger may need replacement.
