is it okay to use my makita cordless drill in the rain really quick?

Diagnosis

The Makita XFD131 is not an IP-rated (Ingress Protection) tool, meaning it has no specialized seals to prevent moisture from entering the internal chassis. When you use this drill in the rain, water penetrates the ventilation ports of the motor housing and the battery terminal interface. Because the XFD131 utilizes a brushed DC motor and a basic electronic trigger switch, water droplets create conductive bridges across these components. This leads to "arcing," where electricity jumps between points it shouldn't, causing immediate localized burns on the circuit board or a complete short of the trigger assembly. Furthermore, the 18V LXT battery terminals are exposed. Rainwater is rarely pure; it contains minerals and pollutants that make it highly conductive. If water bridges the positive and negative terminals of the battery while it is seated in the drill, it can trigger a massive current draw. This can weld the internal battery protection circuit (PCM) shut or, in worst-case scenarios, lead to thermal runaway where the lithium cells overheat and vent gas or ignite. Confirming damage usually involves noticing a "stuttering" trigger, a smell of ozone or burning plastic, or the battery refusing to charge in the LXT charger after the event.

How to Fix It

If you have already exposed your XFD131 to rain, or if you are forced to work in a damp environment, follow these strict recovery and prevention steps:

1. Immediately remove the 18V LXT battery from the tool. Do not attempt to "test" if the drill still works while it is wet, as this is when the most critical short-circuits occur.
2. Use a canister of compressed air or a low-pressure air compressor to blow out the motor vents and the battery terminal slot. Focus on the area around the trigger switch and the rear of the motor housing.
3. Wipe down the gold-plated battery terminals using a clean, lint-free microfiber cloth and a small amount of 90% isopropyl alcohol to remove any mineral deposits left by rainwater.
4. Place the tool in a warm, dry area with a dehumidifier or a fan blowing directly across the vents for at least 12 to 24 hours. Do not use a high-heat blow dryer, as this can warp the plastic housing or melt the internal wire insulation.
5. Once completely dry, insert the battery and test the trigger slowly. If the tool oscillates or smells of burning, remove the battery immediately and seek professional service.

If That Didn't Work

• Replace the Trigger Switch: If the drill is powered on but the speed control is erratic or the tool won't start, the trigger assembly has likely suffered corrosion or a short. This part must be replaced entirely; cleaning it with contact cleaner rarely solves the problem if the internal membrane is breached.
• Inspect the Battery PCM: If the drill works with a different LXT battery but the original battery won't charge, the internal Protection Circuit Module (PCM) has likely tripped or fried. Since LXT batteries are sealed units, this typically requires replacing the entire battery pack for safety reasons.
• Clean the Commutator: If the motor is sparking excessively (visible through the vents) or rotating slowly, moisture may have caused carbon buildup on the commutator. Use a specialized commutator cleaning solvent and a soft brush to clear the debris.
• Check for Internal Oxidation: Disassemble the plastic clamshell housing using a T10 Torx driver. Inspect the copper wiring for green oxidation (verdigris). If found, clean the affected areas with a precision cotton swab dipped in electronic contact cleaner.

Heads Up

• Never store your XFD131 in a damp basement or an open-air garage during humid months; moisture buildup can corrode the internal switches even if the tool never touches rain.
• If you frequently work in the rain, invest in a "tool skin" or a waterproof wrap, but ensure the motor vents remain unobstructed to prevent overheating.
• Always store your 18V LXT batteries in a dry, temperature-controlled environment; exposing them to extreme cold and then sudden moisture can cause internal condensation.
• Avoid using "waterproof" sprays (like silicone) on the tool's exterior, as these can actually trap moisture inside the housing once it does penetrate, preventing the tool from drying out naturally.