What does the red flashing light mean? The flashing red light on your Greenworks charger might frustrate you. After all, you just used your tool and want to put it up for storage.
However, when you try to do that, indicator lights flash red, stopping you in tracks and indicating something isn’t right. Don’t give up on the charger or the battery. The red flashing light indicate a diagnostic.
A little bit of understanding will save your equipment and your money. Most folks first think it is hardware failure, assuming the red light mean it must be broken. Typically that is not the case.
The battery and the charger is using a safety protocol to talk to each other. Something the system doesn’t like are happening so it won’t charge. This protects both your safety and health of the battery.
Knowing what flashing lights mean will tell you whether it’s a simple fix or something more serious. Most of those flash codes is actualy user error and not a defect in the units themselves.
Quick Fixes For Flashing Red Charger Lights
Temperature Effects on Charging
First check the temperature. Cold and heat affects lithium-ion batteries. Too cold or too hot and they simply say no to charging.
Too warm for the battery pack? Maybe you just used tool on a hot day out in the sun? Flashing red mean the charger says it’s not going to take a charge until that battery get cooler. If you take it from a cool garage in the middle of winter, the same thing happen.
Batteries won’t accept electrons when they are extremely cold. Give it some time (about an hour) in temperate room. It’ll get green light.
That’s the most common culprit, and simplest one to fix.
Cleaning Contact Pins
Now check connection points. Most chargers has contact pins on both charger and battery. Soil and other crud can accumulate there. A thin film of resistive dirt and grass clippings, workshop grit and so forth are common. The charger see this as a potential voltage drop or incomplete circuit.
It reads it as a fault. Remove the battery and examine the metal contacts with care. Clean them gently with a soft brush or rag. Wipe off the contacts on your charger too. Often that simple cleaning fix the charger/battery link immediately. Don’t think skipping this little housekeeping chore wouldn’t of cause bigger issues.
That is not true. Don’t overlook the grunge.
Checking Battery Age and Cycle Count
Check how old it is, what its cycle count are. All batteries wears out over time. A few-year-old Greenworks battery might have cells with reduced capacity. That causes protection circuit to kick in.
The charger sense high internal resistance. It won’t work and will not charge. It refuse to charge to prevent overheating or cell swelling. That’s the end of the line for that particular pack. There are no tricks to cool or clean that dead cell. Replace the battery. Look at the manufacturer’s warranty. Swap it out if under warranty. If not, plan on buying a replacement. Better to buy a battery than try to make it charge.
Testing the Charger Unit
Test the charger. It might not be environment and it might not be the battery. It could be charger unit has failed internally. Take a known good battery and plug it into the charger. Does it cause red flash? If so, then the charger is bad. Now take the problem battery and try it in a working charger. If it will charge okay in that one, then it was your original charger. Compared to batteries, Greenworks chargers is pretty cheap. Often times it’s cheaper just to buy a new one.
The flashing red light isn’t a condemnation, it’s a conversation. What is the light telling you? Run the temperature test. Check the contacts for cleanliness. Test each component separately. Odds are your gear require care or patience. Respect the safety signals your tools send you and keep ’em ready to work.