DEWALT DCF900 20V Max* 1/2" High Torque Impact Wrench

Instruction Manual / Guide D'utilisation / Manual de instrucciones

This impact wrench is designed for professional impact fastening and drilling applications. The impact function makes this tool particularly useful for driving fasteners in wood, metal, and concrete.

Components

Refer to Figure A for component identification:

• 1. Trigger switch: Activates the tool and controls variable speed.
• 2. Forward/reverse control button: Selects the tool's rotation direction (forward, reverse) and acts as a lock-off button.
• 3. Anvil: The part that holds the socket for fastening.
• 4. Main handle: Primary grip for the tool.
• 5. Battery release button: Used to detach the battery pack from the tool.
• 6. Battery pack: Provides power to the tool.
• 7. Worklight: LED light that illuminates the work area.
• 8. Worklight switch: Controls the brightness and on/off state of the worklight.
• 9. Mode selector: Allows selection of different speed modes or Precision Wrench™ mode.

Safety Information

General Power Tool Safety Warnings

• ⚠️ WARNING: Read all safety warnings and instructions. Failure to follow may result in electric shock, fire, or serious injury.

• ⚠️ WARNING: To reduce the risk of injury, read the instruction manual.

• SAVE ALL WARNINGS AND INSTRUCTIONS FOR FUTURE REFERENCE.

• The term "power tool" refers to both corded and battery-operated tools.

Work Area Safety

• Keep work area clean and well lit. Cluttered or dark areas invite accidents.
• Do not operate power tools in explosive atmospheres (e.g., presence of flammable liquids, gases, or dust). Power tools create sparks that can ignite dust or fumes.
• Keep children and bystanders away from the operating area. Distractions can lead to loss of control.

Electrical Safety

• Ensure power tool plugs match the outlet. Never modify the plug. Do not use adapter plugs with earthed tools.
• Avoid body contact with earthed or grounded surfaces (pipes, radiators, refrigerators).
• Do not expose power tools to rain or wet conditions. Water ingress increases the risk of electric shock.
• Do not abuse the cord. Never use the cord for carrying, pulling, or unplugging. Keep cord away from heat, oil, sharp edges, or moving parts. Damaged or entangled cords increase electric shock risk.
• When operating outdoors, use an extension cord suitable for outdoor use.
• If operating in a damp location is unavoidable, use a Ground Fault Circuit Interrupter (GFCI) protected supply.

Personal Safety

• Stay alert, watch what you are doing, and use common sense. Do not use when tired or under the influence of drugs, alcohol, or medication.
• Use personal protective equipment (PPE): Always wear eye protection. Use dust masks, safety shoes, hard hats, or hearing protection as appropriate for the conditions.
• Prevent unintentional starting: Ensure the switch is in the OFF position before connecting to power or battery, picking up, or carrying the tool.
• Remove any adjusting key or wrench before turning the power tool on.
• Do not overreach. Keep proper footing and balance at all times for better control.
• Dress properly: Do not wear loose clothing or jewelry. Keep hair, clothing, and gloves away from moving parts.
• If dust extraction/collection facilities are provided, ensure they are connected and used properly to reduce dust-related hazards.
• Do not let familiarity gained from frequent use lead to complacency. A careless action can cause severe injury.

Impact Wrench Specific Safety Warnings

• Hold the tool by insulated gripping surfaces when fastening near hidden wiring. Fasteners contacting a "live" wire can make exposed metal parts "live" and cause electric shock.
• Wear ear protectors during use.

• ⚠️ WARNING: Impact wrenches are NOT torque wrenches. DO NOT use this tool for tightening fasteners to specified torques. Use a calibrated torque measurement device (e.g., torque wrench) for proper torque.

• Wear safety goggles or other eye protection. Hammering and drilling operations cause chips to fly, which can cause permanent eye damage.

• Do not operate for long periods. Vibration can be harmful to hands and arms. Use gloves for cushioning and take frequent rest periods.

• Accessories and tools get hot during operation. Wear gloves when touching them.

Additional Safety Information

• ⚠️ WARNING: Never modify the power tool or any part of it. Damage or personal injury could result.

• ⚠️ WARNING: ALWAYS use safety glasses. Everyday eyeglasses are NOT safety glasses. Use a face or dust mask if cutting is dusty.

• ALWAYS WEAR CERTIFIED SAFETY EQUIPMENT: ANSI Z87.1 eye protection, ANSI S12.6 hearing protection, NIOSH/OSHA/MSHA respiratory protection.

• WARNING: Dust from certain activities (sanding, sawing, grinding, drilling) may contain chemicals known to cause cancer, birth defects, or reproductive harm (e.g., lead, silica, arsenic, chromium). Reduce exposure by working in a well-ventilated area with approved safety equipment (dust masks). Wear protective clothing and wash exposed areas with soap and water. Direct particles away from face and body.

• Use the appropriate dust extractor vacuum to remove dust. Failure to do so can contaminate the working environment or increase health risks.

• Use clamps or other practical ways to secure and support the workpiece. Holding the workpiece by hand or against your body is unstable and may lead to loss of control.

• Avoid air vents, as they often cover moving parts. Loose clothing, jewelry, or long hair can get caught.

• ? CAUTION: When not in use, place the tool on its side on a stable surface.

Symbols and Definitions

The label on your tool may include symbols. Key safety alert symbols include:

• DANGER: Imminent hazard, death or serious injury.

• WARNING: Potential hazard, death or serious injury.

• CAUTION: Potential hazard, minor or moderate injury.

• (No word): Safety-related message.

• NOTICE: Practice not related to personal injury, may result in property damage.

Operation

Intended Use

This impact wrench is designed for professional impact fastening and drilling applications. The impact function makes it useful for driving fasteners in wood, metal, and concrete.

Proper Hand Position (Fig. G)

⚠️ WARNING: To reduce the risk of serious personal injury, ALWAYS use proper hand position as shown and hold securely to anticipate sudden reactions. Proper hand position requires one hand on the main handle.

Variable Speed Trigger Switch (Fig. A)

To turn the tool on, squeeze the trigger switch. To turn off, release the trigger switch. The tool is equipped with a brake that stops the anvil when the trigger is fully released. The variable speed switch allows selection of the best speed for an application. For maximum tool life, use variable speed only for starting holes or fasteners. Continuous use in the variable speed range is not recommended as it may damage the switch.

Forward/Reverse Control Button (Fig. A)

This button determines the tool's direction and serves as a lock-off button. Select forward rotation by pressing the button on the right side of the tool. Select reverse by pressing the button on the left side. The center position locks the tool OFF. Ensure the trigger is released when changing the button position. A click on start-up after changing direction is normal.

Worklight (Fig. A, D)

The worklight is activated when the variable speed trigger is depressed. Pressing the worklight switch repeatedly cycles through low illumination, high illumination, and off. The worklight is for illuminating the immediate work surface only.

Usage (Fig. A)

? CAUTION: Ensure the fastener and/or system will withstand the torque generated by the tool. Excessive torque may cause breakage and possible personal injury.

1. Place the accessory on the fastener head. Keep the tool pointed straight at the fastener.
2. Press the variable speed trigger switch to start operation. Release to stop.
3. Always check torque with a torque wrench, as fastening torque is affected by many factors, including: Voltage (low voltage reduces torque), Accessory size, Bolt size, Bolt condition (threads free of rust/debris), Material type and surface finish, Fastening time (longer time increases torque).

Specifications

Maintenance

⚠️ WARNING: Turn unit off and remove battery pack before making any adjustments or removing/installing attachments or accessories. Accidental start-up can cause injury.

General Maintenance

Your DEWALT power tool is designed for long operation with minimum maintenance. Proper tool care and regular cleaning ensure satisfactory operation.

Cleaning

• ⚠️ WARNING: Blow dirt and dust out of all air vents with clean, dry air at least once a week. Wear ANSI Z87.1 approved eye protection.

• ⚠️ WARNING: Never use solvents or harsh chemicals for cleaning non-metallic parts. Use a cloth dampened only with water and mild soap. Do not let liquid get inside the tool.

Batteries and Chargers

Important Safety Instructions for All Battery Packs

• ⚠️ WARNING: Read all safety warnings, instructions, and cautionary markings.

• Do not charge or use the battery pack in explosive atmospheres.

• NEVER force the battery pack into the charger. DO NOT modify the battery pack.

• Charge the battery packs only in DEWALT chargers.

• DO NOT splash or immerse in water or other liquids. DO NOT allow water or any liquid to enter the battery pack.

• Do not store or use where temperature may reach or exceed 104°F (40°C). Store in a cool, dry location.

• NOTE: Do not store battery packs in a tool with the trigger switch locked on. Never tape the trigger switch in the ON position.

• Do not incinerate the battery pack, even if severely damaged or worn out. It can explode in a fire.

• Do not expose battery pack or tool to fire or excessive temperature (above 265°F / 130°C).

• Follow all charging instructions and temperature ranges.

• If battery contents contact skin, wash immediately with mild soap and water. If in eyes, rinse with water for 15 minutes. Seek medical attention if needed.

• Opened battery cells may cause respiratory irritation. Provide fresh air.

• Battery liquid may be flammable.

• Never attempt to open the battery pack. Do not crush, drop, or damage the battery pack. Return damaged packs for recycling.

Storage Recommendations

Store in a cool, dry place, away from direct sunlight and excess heat or cold. Store the fully charged battery pack out of the charger.

Battery Pack Cleaning Instructions

Clean exterior with a cloth or soft non-metallic brush. Do not use water or cleaning solutions.

Fuel Gauge Battery Packs (Fig. B)

Some battery packs include a fuel gauge. LED lights indicate approximate charge level when the button is pressed. This does not indicate tool functionality.

Transportation

⚠️ WARNING: Fire hazard. Do not store, carry, or transport the battery pack where metal objects can contact exposed battery terminals. Protect terminals. Li-ion battery packs are prohibited in checked baggage on airplanes.

Shipping the DEWALT FLEXVOLT® Battery Pack

Use the battery cap when shipping the battery pack. This converts the pack to three separate 20V batteries. If shipping without the cap or in a tool, the pack is one battery.

The RBRC® Seal

Take spent battery packs to an authorized DEWALT service center or local retailer for recycling. Visit www.call2recycle.org for more information.

Important Safety Instructions for All Battery Chargers

• ⚠️ WARNING: Read all safety warnings, instructions, and cautionary markings.

• Do not attempt to charge the battery pack with chargers other than DEWALT chargers.

• Chargers are not intended for uses other than DEWALT rechargeable battery packs.

• Do not expose the charger to rain or snow. Do not allow water or liquid to enter the charger.

• Pull by the plug, not the cord, when disconnecting the charger.

• Ensure the cord is not a tripping hazard or subject to damage.

• Use extension cords only if necessary. Use proper gauge outdoor extension cords.

• Do not block charger ventilation slots. Do not operate with a damaged cord/plug.

• Do not operate if dropped or damaged. Take to an authorized service center.

• Do not disassemble the charger. Take to an authorized service center for service or repair.

• Charger is designed for 120V household power.

• Keep foreign conductive materials away from charger cavities and ventilation slots.

• Always unplug the charger when no battery pack is inserted.

Charging a Battery (Fig. C)

1. Plug the charger into an appropriate outlet.
2. Insert and fully seat the battery pack. The red charging light(s) will blink continuously while charging.
3. Charging is complete when the red charging light(s) remain continuously ON. The battery pack can remain in the charger.

4. ⚠️ WARNING: Only charge batteries in air temperature between 40°F (4.5°C) and 104°F (40°C).

5. Charger will not charge a faulty battery pack (indicated by light(s) staying OFF). Take charger and battery pack to an authorized service center.

Hot/Cold Pack Delay

If the charger detects a battery pack that is too hot or too cold, it automatically starts a Hot/Cold Pack Delay, suspending charging until the battery pack reaches an appropriate temperature. This feature ensures maximum battery pack life. A cold battery pack may charge slower than a warm one. The delay is indicated by a blinking red light and a continuously ON yellow light. Once the battery pack reaches the correct temperature, the yellow light turns OFF and charging resumes.

DCB118 and DCB1112 Chargers

These chargers are equipped with an internal fan designed to cool the battery pack. The fan turns on automatically when needed.

Electronic Protection System

Li-Ion tools are designed with an Electronic Protection System to protect the battery pack against overloading, overheating, or deep discharge. The tool will automatically turn off and the battery pack will need to be recharged.

Important Charging Notes

• For longest life and best performance, charge when air temperature is between 65°F–75°F (18°C–24°C). DO NOT charge below 40°F or above 104°F.

• The charger and battery pack may become warm during charging. This is normal.

• To facilitate cooling after use, avoid placing the charger or battery pack in warm environments.

Accessories and Repairs

Accessories

⚠️ WARNING: Use only DEWALT recommended accessories. Using other accessories may be hazardous and could cause injury.

Impact Accessories

⚠️ WARNING: Use only impact accessories. Non-impact accessories may break and cause a hazardous condition. Inspect accessories for cracks before use.

Repairs

Charger and battery packs are not serviceable. Service should only be performed by a DEWALT factory service center or an authorized service center using identical replacement parts.

Registration and Warranty

Register Online

Register your product online at www.dewalt.com for efficient warranty service, confirmation of ownership, and safety notifications.

Three Year Limited Warranty

For warranty terms, visit www.dewalt.com/Legal/Warranty/3-Year-Limited-Warranty. Contact Customer Service for details.

Free Warning Label Replacement

Call 1-800-4-DEWALT for replacement warning labels if they become illegible or are missing.