i got my dewalt drill wet, not soaked but some spray from rain. is it ruined? what should i do?

Diagnosis

Water ingress in the DeWalt DCD771C2 is a critical failure risk because the tool is not IP-rated for water resistance. When rain spray enters the chassis, the moisture settles on the printed circuit board (PCB) and the trigger switch assembly. The primary danger is not just a short circuit, but "electrolytic corrosion," where the DC current from the 20V battery reacts with water and minerals to eat through the copper traces on the circuit board in a matter of hours.

If you attempt to pull the trigger while the internal components are damp, you risk a "hard short," which can permanently fry the MOSFETs (metal-oxide-semiconductor field-effect transistors) that control the motor speed. To confirm if water has penetrated the housing, look for droplets around the vent holes of the motor housing or moisture trapped behind the transparent plastic of the trigger switch. If you see beads of water inside the trigger housing, the moisture has reached the electronic control system.

How to Fix It

Follow these precise steps to salvage the tool and prevent a permanent electrical short.

1. Immediate Power Isolation: Immediately slide the battery release button and remove the 20V Max battery pack. Do not press the trigger to "test" if it still works; doing so can send current through a water-bridged circuit and cause an immediate burnout.
2. External Decontamination: Use a lint-free microfiber cloth to wipe all exterior surfaces. Pay special attention to the seams where the plastic clamshell housing meets, as water often clings to these edges and seeps inward via capillary action.
3. Forced Air Evacuation: Use a canister of compressed air or a shop vac on "blow" mode. Direct the air into the motor vents (the slots near the rear of the drill) and around the trigger assembly to push out any trapped droplets.
4. Passive Dehydration: Place the drill (without the battery) in a warm, low-humidity environment. Do not use a high-heat hairdryer, as this can warp the plastic housing or melt the internal wire insulation. A room with a dehumidifier or a gentle desk fan blowing directly across the vents is ideal.
5. The 48-Hour Rule: Leave the tool to dry for a minimum of 48 hours. Moisture can linger in the tight crevices of the planetary gear assembly and the trigger switch long after the exterior feels dry.
6. Battery Inspection: Wipe the battery terminals with a dry cloth. Inspect the gold-plated contact points for any green or white powdery residue (oxidation). If present, clean them gently with a cotton swab dipped in 90% isopropyl alcohol.

If That Didn't Work

If you reinsert the battery after 48 hours and the drill exhibits erratic behavior, try these advanced recovery steps:

• Contact Cleaner Treatment: If the trigger feels "sticky" or the motor stutters, use a non-conductive electronic contact cleaner (such as CRC QD Electronic Cleaner). Spray it liberally into the trigger switch assembly and the motor vents. This displaces remaining water and removes mineral deposits that cause shorts.
• Internal Component Drying: If you are comfortable with basic tool disassembly, remove the screws from the outer housing to open the clamshell. Use a soft brush and isopropyl alcohol to gently clean any visible corrosion on the PCB before reassembling.
• Battery Cycle Test: If the drill won't start, test the battery on a different 20V DeWalt tool. If the battery works elsewhere, the internal switch of the DCD771C2 has likely shorted and will require a replacement trigger assembly (Part #D24453).
• Motor Lubrication: If the drill makes a grinding noise after drying, the moisture may have emulsified the grease in the gear head. You may need to open the gear housing and apply a small amount of lithium-based grease to the planetary gears.

Heads Up

• Avoid Rice: Never put your power tool in a bag of rice. Rice dust can enter the motor and gear assembly, creating a gritty paste when mixed with moisture that will accelerate wear on the internal brushes.
• Battery Safety: If the battery pack itself was submerged or heavily sprayed, do not charge it until it is completely dry. Charging a wet lithium-ion battery can lead to thermal runaway or permanent cell failure.
• GFCI Requirement: When charging your batteries after a rain event, always use a GFCI (Ground Fault Circuit Interrupter) outlet to prevent electric shock in case the charger has absorbed moisture.
• Storage Tip: To prevent future moisture damage, store your DCD771C2 in a hard plastic case or a dry tool box rather than leaving it on a workbench in an open garage.