avid power drill battery won't charge, charger light doesn't come on. help?

Diagnosis

The total absence of an LED indicator on the Avid Power 20V charger typically signifies a complete break in the electrical circuit, meaning the charger is not receiving power or the internal safety relay has tripped. Unlike a blinking red light (which indicates a defective battery), a dark LED suggests that the charger's internal logic board is not being energized. This is often caused by a failed AC-DC transformer within the charger brick or a physical disconnection between the battery terminals and the charger's contact pins.

To confirm the root cause, first perform a "cross-test." Plug the charger into a different outlet on a separate circuit breaker to rule out a tripped GFCI outlet. If the light remains off even without a battery inserted, the charger itself has likely suffered a component failure. If the light only stays off when the battery is inserted, the battery's internal Protection Circuit Module (PCM) has likely triggered a "deep discharge" state, where the voltage has dropped below the minimum threshold required for the charger to recognize the pack, effectively "cloaking" the battery from the charger.

How to Fix It

Follow these precise steps to restore power to your charging system:

1. Isolate the Power Source: Unplug the charger from the wall. Check the prongs for any signs of bending or carbon buildup. Plug it into a known-working 120V AC outlet—avoid using power strips or surge protectors for this test, as these can sometimes limit the initial current draw required to wake a dormant battery.
2. Inspect the Contact Rails: Take a dry microfiber cloth or a cotton swab dipped in 90% isopropyl alcohol. Clean the two metal contact rails on the top of the 20V battery pack and the corresponding spring-loaded pins inside the charger. Even a thin layer of dust or oxidation can prevent the circuit from closing.
3. Perform a Hard Reset: With the charger plugged in and the battery removed, wait 60 seconds. Firmly slide the battery into the charger, applying downward pressure until you hear a distinct "click" from the locking tabs. Ensure the battery is flush against the charger housing; if there is a gap of even 1-2mm, the pins will not engage.
4. Thermal Stabilization: If the drill was used in a cold garage or left in a hot car, the internal thermistor will block charging. Move both the charger and battery to a room stabilized at 70°F (21°C) for at least two hours before attempting to charge again.

If That Didn't Work

• Jumpstart the Battery: If the battery is "deep discharged" (below 15V for a 20V pack), the charger won't see it. If you have a second working Avid Power battery, you can briefly connect the positive terminal of the full battery to the positive of the dead one using a heavy-gauge wire for 30 seconds. This "surface charge" can often raise the voltage enough for the official charger to recognize the battery and begin a standard cycle.
• Check for Terminal Compression: Inspect the gold-plated pins inside the charger. Use a small flashlight to see if any pins are stuck in the "down" position. If a pin is stuck, gently nudge it upward with a plastic toothpick to ensure it can make contact with the battery rail.
• Replace the Charger Unit: Because the Avid Power 20V charger is a sealed plastic unit, internal capacitor failures cannot be repaired. If the LED remains dark across multiple outlets and with multiple batteries, the internal transformer has failed and the charger must be replaced.
• Test for Battery Cell Failure: Use a digital multimeter to measure the DC voltage across the battery terminals. If the reading is below 14V, the internal lithium-ion cells may have degraded beyond recovery, and the battery pack will need to be replaced.

Heads Up

• Avoid Deep Discharge: Never store your Avid Power batteries when they are completely dead. Lithium-ion cells that drop below a certain voltage threshold can permanently chemically degrade, making them impossible to recharge.
• Avoid Overcharging: Once the LED turns solid green, remove the battery. Leaving the battery on the charger for days at a time can stress the cells and shorten the overall lifespan of the pack.
• Storage Temperature: Store your batteries in a cool, dry place. Extreme heat (above 105°F) can warp the plastic casing and damage the internal PCM, while extreme cold can cause permanent capacity loss.
• Cleanliness: Keep the battery terminals free of sawdust and metal shavings. Conductive debris on the rails can cause a short circuit that may blow the internal fuse of the charger.