Quick answer
- A red blinking light on your DeWalt charger indicates a fault with the battery pack.
- Ensure the battery is not too hot or cold; lithium-ion batteries refuse to charge below ~32°F (0°C).
- Check for any visible damage on the battery pack, such as swelling or corrosion.
- If the battery appears fine but still shows a fault, consider replacing it.
Symptoms
When you connect a battery to a DeWalt charger, such as the DCB115 or DCB118, you may observe the following LED patterns:
- Red blinking light: This indicates that the charger has detected a fault with the battery pack.
- No sound or activity: The charger remains inactive, indicating it is not charging the battery.
- Behavior under load: If the battery was previously working but now shows a fault, the tool may fail to operate or exhibit reduced performance.
Quick checks
Before diving into deeper troubleshooting, perform these quick checks:
- Temperature check: Ensure the battery is not excessively hot or cold. If the battery feels hot, let it cool for at least 30 minutes. If cold, warm it to room temperature.
- Visual inspection: Look for any signs of physical damage, such as swelling, punctures, or corrosion on the battery terminals.
- Charger functionality: Test the charger with a different, known-good battery to confirm that the charger is functioning correctly.
- Battery connection: Ensure the battery is seated properly in the charger, making good contact with the terminals.
- Power source: Verify that the charger is plugged into a working outlet.
Step-by-step fix
- Remove the battery: Always start by disconnecting the battery from the charger to prevent any electrical issues during troubleshooting.
- Inspect the battery: Check for any visible damage. If the battery is swollen, punctured, or corroded, it should not be used and must be recycled.
- Check the charger: Use a different battery to see if the charger functions correctly. If it does, the original battery is likely faulty.
- Temperature adjustment: If the battery is cold, allow it to warm up to at least 32°F (0°C) before attempting to charge it again. If it’s hot, let it cool for 30 minutes.
- Reconnect and test: After ensuring the battery is at a suitable temperature and free of damage, reconnect it to the charger and observe the LED indicator.
- Replace the battery if needed: If the red blinking light persists, consider replacing the battery, as it may be defective.
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If it still isn't working
If the battery continues to show a red blinking light after following the steps above, it may be time to escalate:
- Warranty check: Review the warranty terms for your battery. DeWalt batteries typically have a 3-year warranty, which may cover defects.
- Service center: Contact a local DeWalt service center for further diagnosis and potential repair.
- Replacement: If the battery is out of warranty or deemed unrepairable, consider purchasing a new battery.
FAQ
Why is my DeWalt battery charger blinking red?
A red blinking light indicates a fault with the battery pack. This could be due to temperature issues, physical damage, or internal failure.
Can I use my DeWalt battery in cold weather?
Lithium-ion batteries may refuse to charge or discharge below ~32°F (0°C). Allow the battery to warm up to room temperature before using or charging.
What should I do if my battery is swollen?
Do not use a swollen battery. It poses a safety risk. Recycle it at a designated drop-off location.
How can I tell if my charger is working?
Test the charger with a different, known-good battery. If it charges that battery without issue, the original battery may be faulty.
What if my charger shows a different LED pattern?
Refer to the specific LED fault patterns for your charger model. Different models may have different meanings for their LED indicators. For example, a fast blinking red light may indicate a different issue than a steady red light.