4 LEDs Flashing
DeWalt Power Tool
Severity: ModerateWhat Does This Error Mean?
DeWalt 20V Max batteries flash all 4 LEDs together when the pack is too hot to operate safely.
The protection circuit shuts the battery off until it cools below the safe threshold.
The fix is to remove the battery from the tool, place in a cool indoor area (not direct sun), and wait 30-60 minutes.
The battery resumes normal operation once temperature drops.
Affected Models
- DeWalt 20V Max DCB200 series
- DeWalt 20V Max DCB201 (1.5 Ah)
- DeWalt 20V Max DCB203 (2.0 Ah)
- DeWalt 20V Max DCB205 (5.0 Ah)
- DeWalt 20V Max DCB206 (6.0 Ah)
- DeWalt FlexVolt DCB606
Common Causes
- Heavy continuous use under load
- Hot weather plus heavy use
- Battery left in direct sun
- Charging immediately after heavy use
- Internal cell imbalance generating heat
- Battery aged with reduced thermal capacity
How to Fix It
-
Remove battery from tool.
Eject the battery from the tool.
Set it on a cool surface — concrete floor, shaded shelf.
Avoid placing on hot pavement, near heat sources, or in a closed vehicle. -
Wait 30-60 minutes.
DeWalt batteries cool from operating temperature in roughly 30 minutes indoors.
In hot weather it may take longer.
Press the LED button — when 4 LEDs no longer flash, the battery has cooled enough. -
Do not charge a hot battery.
Putting a hot battery on the charger triggers the charger's hot-pack delay (charger flashes red).
The charger holds the battery until it cools, then begins charging.
This is normal protection, not a fault. -
Reduce continuous load.
Continuous high-current use (large hole saw, high-torque impact) generates heat fast.
Take 60-second breaks every few cuts to let the battery cool.
Rotate between two batteries on heavy jobs to keep both cool. -
Avoid direct sun storage.
Batteries left in a tool sitting in the sun reach 130°F+ within minutes.
Store tools and spare batteries in shade — toolbox in shade is fine, truck bed in sun is not. -
Check for imbalance.
If 4 LEDs flash even when the battery feels cool, the cells inside are imbalanced.
An imbalanced pack heats unevenly and trips the over-temp protection prematurely.
This is a sign of battery wear — typically appears after 2-3 years of heavy use.
Replacement is the only fix. -
Test the battery.
Once cool, press the gauge button — should show 1-4 LEDs solid (charge level).
Place in a tool and run.
If 4 LEDs flash again within 1-2 minutes of normal use, the pack is failing — replace.
Frequently Asked Questions
Is the battery damaged after over-temp?
A single over-temp event is not damaging — the protection cuts power before damage occurs.
Repeated over-temps shorten battery life, especially if combined with hot storage.
Cool storage and operation extend pack life dramatically.