Ryobi P118 Charger Blinking Red Light — What It Means and How to Fix It

Quick answer

• The Ryobi P118 charger has two LEDs — red and green. You have to read them together; the red alone tells you nothing.
• Red on + green flashing = normal charging in progress. This is fine.
• Red flashing alone (green off) = evaluation/testing mode — the pack is too hot, too cold, or deeply discharged. The charger is waiting. Move the battery to room temperature and retry in 30 minutes.
• Red fading (smooth pulse, green off) = defective battery or defective charger. If a known-good battery does the same thing, the charger is the problem.
• Red off + green solid = charging complete, in maintenance mode.
• A single red or green LED reading is not enough — check what the other LED is doing.

Symptoms

You set the P118 charger on the workbench, plug a Ryobi 18V ONE+ pack in, and the red LED starts blinking. Maybe the green is off entirely. Maybe the green is also doing something. The charger isn't finishing the cycle.

The confusion here is that the P118 uses a combined two-LED scheme. Red blinking by itself is not the same as red-on with green-flashing. These mean completely different things.

Quick checks

1. Look at both LEDs simultaneously. Note whether each LED is on (solid), flashing (sharp on/off), fading (smooth slow pulse), or off.
2. Check the battery temperature. If the pack just came off the tool after heavy use, or has been sitting in a cold garage below 40°F (4°C), that's likely the cause.
3. Try a second battery if you have one. If the second battery charges normally, the first pack is the issue. If the second battery also triggers the same blinking pattern, the charger may be faulty.
4. Check the contacts. Wipe the battery terminals and charger contacts with a dry cloth. Dirty contacts can prevent the charger from reading the pack.
5. Confirm the charger is seated on a flat, stable surface. Partial battery engagement can trigger the evaluation mode.

Step-by-step fix

1. Remove the battery from the charger. Let both the charger and the battery rest for a few minutes before troubleshooting.

2. Evaluate the battery temperature. If the pack was in a car, shed, or outside in cold weather, bring it indoors. The P118 won't charge a pack below approximately 40°F (4°C). If it was just used hard and is warm to the touch, set it aside for 30 minutes to cool.

3. Re-insert the battery and observe both LEDs. Per the P118 manual:

   • Red on + green flashing = charging normally. Leave it alone.
   • Red flashing + green off = evaluation mode. The charger detected a temperature or deep-discharge condition. Give it time.
   • Red fading + green off = suspect a defective pack.

4. Wait up to 30 minutes in evaluation mode. Per Ryobi's P119 manual (same LED logic applies): if the charger stays in evaluation mode for more than 30 minutes at room temperature, the battery pack is likely defective and will not recover on this charger.

5. Clean the contacts and retry. Use a dry toothbrush or contact cleaner on both the battery terminals and the charger slots.

6. Test with a known-good battery. If a healthy pack charges fine on this charger, the original battery is the issue. If your good pack also triggers the evaluation state, the charger itself needs replacing.

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If it still isn't working

If the battery stays in evaluation mode for 30+ minutes at room temperature — and a known-good battery charges fine on the same charger — the pack has likely reached end of life. Ryobi covers 18V ONE+ batteries under a 3-year limited warranty. If the pack is within that window and you purchased it from an authorized retailer, contact Ryobi customer support or visit ryobitools.com/support to start a warranty claim.

If the charger is the suspect (multiple batteries fail on it, or you see the red-fading pattern with a battery you know is good), the charger is also covered under Ryobi's 3-year limited warranty.

A deeply discharged pack — one that sat unused for months — sometimes won't recover regardless. Li-ion cells that drop below a certain voltage threshold trip the BMS in a way that's not always reversible.

FAQ

What does red blinking mean on a Ryobi P118 charger?

Red blinking alone (with the green LED off) is the evaluation state. The charger detected that the pack is too hot, too cold, or deeply discharged and is waiting for conditions to improve. This is a recoverable state in most cases — bring the battery to room temperature (65°F-75°F / 18°C-24°C) and retry. If it persists beyond 30 minutes at room temperature, the pack may be defective.

Why is my Ryobi charger blinking red but the battery was just charging fine yesterday?

Temperature is the most common cause. If the battery or charger got cold overnight (below 40°F / 4°C), the P118 will refuse to charge until it warms up. Bring everything indoors for 30 minutes and retry. If temperature isn't the issue, check the battery contacts for corrosion or debris.

Is red-on plus green-flashing a problem on the P118?

No. Red on with green flashing is the normal charging state on the Ryobi P118. The charger is actively charging the pack. That's what it's supposed to look like during a charge cycle. Leave it until the green solid and red off state appears.

My Ryobi charger shows red fading (a smooth slow pulse). What does that mean?

Red fading — a smooth slow pulse, not a sharp blink — indicates a defective battery or defective charger. Test with another battery to isolate which component is at fault. If a healthy pack charges fine on the same charger, the fading pack is defective. If all batteries show the fading pattern, replace the charger.

Can I use a P118 charger for Ryobi 40V batteries?

No. The Ryobi P118 is a 18V ONE+ charger and will not charge 40V batteries. The 18V ONE+ and 40V platforms use different physical interfaces — the connectors do not cross-fit. For 40V packs, use a Ryobi 40V charger (OP400 or similar).