Battery Charger Blinking Red Light — What the LED Code Means

Quick answer

• A blinking red light on your DeWalt charger indicates a fault with the battery pack.
• Common issues include overheating, cold temperatures, or a defective battery.
• Allow the battery to cool or warm it if it's too cold, then try charging again.
• If the problem persists, consider replacing the battery or contacting customer service.

Symptoms

When using a DeWalt charger, such as the DCB115 or DCB118, you may notice a red blinking light. This indicates that the charger is experiencing a fault. The charger may also emit a slow blinking pattern, which signifies that it is actively charging, but if it shifts to a rapid blink, it typically points to a problem with the battery pack. You may also hear no sounds or clicks from the charger, indicating it is unable to engage the charging process properly.

Quick checks

Before diving into deeper troubleshooting, verify the following:

1. Temperature Check: Ensure the battery is not too hot or too cold. Lithium-ion batteries will not charge below approximately 32°F (0°C) due to a built-in safety mechanism.
2. Battery Connection: Remove and reinsert the battery to ensure a good connection. Sometimes, dirt or debris can prevent proper contact.
3. Charger Functionality: Test the charger with a different battery pack if available. This helps determine if the issue lies with the charger or the battery itself.
4. Visual Inspection: Check the battery for any visible damage, such as swelling, corrosion, or punctures. A damaged battery should never be used.
5. Power Source: Ensure the charger is plugged into a functioning outlet. If possible, test the outlet with another device.

Step-by-step fix

1. Remove the Battery: Always start by disconnecting the battery from the charger. This ensures safety while troubleshooting.
2. Inspect the Battery: Look for any signs of damage, such as swelling or corrosion. If you notice any, do not attempt to charge the battery; recycle it properly.
3. Check Temperature: If the battery feels warm, let it cool for at least 30 minutes before attempting to charge again. If it's cold, warm it to room temperature (above 32°F) before re-inserting it into the charger.
4. Reconnect the Battery: Once the battery is at a suitable temperature, firmly reinsert it into the charger. Ensure it clicks into place to confirm a proper connection.
5. Monitor the LED: Observe the charger’s LED indicator. If it blinks red again, it may indicate a defective battery. If it turns solid red, the battery is charging normally.
6. Consider Replacement: If the battery continues to show a fault after these steps, it may need replacement. Consider purchasing a new battery to restore functionality.

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If it still isn't working

If the charger continues to blink red after following the steps above, it may be time to escalate the issue. Check if your battery is still under warranty. DeWalt typically offers a 3-year limited warranty on batteries. If so, contact DeWalt customer service for assistance or take the battery to an authorized service center for evaluation. If the battery is out of warranty, consider purchasing a replacement.

FAQ

What does a solid red light mean on my DeWalt charger?
A solid red light indicates that the battery is charging. If it remains solid red for an extended period, it may suggest an issue with the battery.

Why is my DeWalt battery not charging?
There are several reasons a DeWalt battery may not charge, including temperature extremes, connection issues, or a defective battery. Check the LED patterns for guidance.

Can I use a different charger for my DeWalt battery?
It is recommended to use the charger specifically designed for your battery platform. For example, DeWalt DCB115 chargers are compatible with 20V MAX, 12V MAX, and FLEXVOLT batteries (most DeWalt 20V MAX chargers handle all three), but no DeWalt charger will accept Milwaukee, Makita, or Ryobi packs.

What should I do if my battery is swollen?
A swollen battery is a sign of failure and should not be used. Dispose of it safely at a recycling location, such as Home Depot or Lowe's.

How can I fix a DeWalt battery that won’t charge?
Start by checking the battery's temperature, connections, and visual condition. If issues persist, consider replacing the battery or consulting customer support. For more detailed troubleshooting, visit our guides on DeWalt battery won’t charge solid red light and DeWalt battery won’t charge fix.