DeWalt 12A-O1C2039 Lawn Mower Manual

The DeWalt 12A-O1C2039 is a 20-inch cordless electric lawn mower powered by a 12Ah battery system, featuring a brushless motor, single-lever height adjustment (1.5" to 4"), 3-in-1 mulching/bagging/side discharge capability, foldable handles for storage, LED headlight for low-light conditions, push-button start, and a weather-resistant construction. Below are key sections for safety, features, assembly, operation, maintenance, and troubleshooting.

1. Features at a Glance 2. Assembly Instructions 3. First-Time Setup 4. Specifications 5. Controls and Operation 6. Cutting Height Adjustment 7. Mulching, Bagging & Discharge 8. Battery & Charging 9. Maintenance & Storage 10. Safety Information 11. Troubleshooting

Features at a Glance

Key components: Brushless motor deck, 12Ah Lithium-ion battery, Charger, Mulching plug, Grass collection bag, Side discharge chute, Height adjustment lever, Safety key.

Feature	Description
Brushless Motor	High-efficiency, low-maintenance power system
12Ah Battery	Provides extended runtime; compatible with DeWalt 20V/60V system
Single-Lever Height Adjust	Adjusts all four wheels simultaneously (1.5" to 4")
3-in-1 Function	Mulch, bag, or side discharge without tools
Foldable Handles	For compact storage and transport
LED Headlight	Illuminates path in early morning or evening
Push-Button Start	Instant start with safety key inserted
Weather-Resistant Deck	Steel construction with corrosion-resistant coating
Battery Fuel Gauge	Displays remaining charge on battery pack
Safety Key	Removable key prevents accidental start-up

Assembly Instructions

Unpack all parts and inspect for damage. Assembly requires basic tools (included).

Attach Lower Handle: Align lower handle with deck brackets; secure with provided bolts and wrench.
Attach Upper Handle: Connect upper handle to lower handle; tighten knobs securely.
Install Grass Bag: Hook bag frame onto rear deck mounts; ensure bag is fully seated.
Install Side Discharge Chute (if needed): Slide chute into side port until it clicks.
Insert Mulching Plug (if needed): Place plug into rear discharge opening.
Install Battery: Insert fully charged battery into battery compartment until it locks.

WARNING! Ensure mower is turned off and battery is removed during assembly to prevent accidental start-up.

First-Time Setup

Prepare mower for initial use.

Charge Battery: Connect charger to battery and AC outlet; charge until indicator shows full (approx. 60 minutes).
Adjust Cutting Height: Set lever to desired height (recommend 3" for first mow).
Select Discharge Mode: Install mulching plug, bag, or side chute based on your preference.
Insert Safety Key: Push safety key into slot near handle.
Test Operation: Press and hold safety handle, then press start button in an open area.

CAUTION! Clear mowing area of stones, sticks, and debris before first use. Wear appropriate safety gear.

Specifications

Cutting Width: 20 inches.
Power Source: DeWalt 20V/60V MAX 12Ah Lithium-ion battery.
Motor Type: Brushless.
Cutting Height Range: 1.5 to 4 inches (7 positions).
Deck Material: Steel with corrosion-resistant finish.
Weight (without battery): 55 lbs.
Runtime (approx.): Up to 60 minutes on fully charged 12Ah battery.
Charging Time: 60 minutes with rapid charger.
Warranty: 3-year limited warranty on mower; 2-year on battery.

Controls and Operation

Main Controls: Safety handle (must be held to run motor), Start/Stop button, Battery release button, Height adjustment lever, Battery fuel gauge.

Starting: Insert safety key. Grip safety handle against upper handle. Press and hold start button. Release start button to stop; release safety handle for emergency stop.

Operation Tips: Mow in straight, overlapping passes. Avoid mowing when grass is wet. For best results, never cut more than 1/3 of grass height at once. Empty bag when full indicator is raised.

Cutting Height Adjustment

Use single lever to adjust all wheels simultaneously.

Locate height adjustment lever on each wheel or central lever.
Pull lever outward and move to desired position (1.5, 2, 2.5, 3, 3.5, 4 inches).
Ensure lever clicks into place on all wheels for even cut.

Tip: For healthier lawn, adjust height seasonally: higher in summer heat, lower in spring/fall.

Mulching, Bagging & Discharge

Convert between modes without tools.

Mulching: Install mulching plug into rear opening. Cuttings are finely chopped and returned to lawn as fertilizer.
Bagging: Remove mulching plug. Attach grass bag to rear mounts. Empty bag when full.
Side Discharge: Remove mulching plug and bag. Install side discharge chute. Cuttings are ejected to the side.

WARNING! Always stop mower and remove battery before changing modes. Ensure attachments are securely installed.

Battery & Charging

Battery: DeWalt 20V/60V MAX 12Ah Lithium-ion. Charger: DeWalt DCB115 Rapid Charger.

Charging: Connect charger to battery and AC outlet. Charger light will flash red, then solid green when complete.
Storage: Store battery at room temperature. For long storage, charge to 50% and store in cool, dry place.
Fuel Gauge: Press button on battery to display remaining charge (LED indicators).

CAUTION! Use only DeWalt chargers and batteries. Do not expose battery to fire, water, or extreme temperatures.

Maintenance & Storage

Regular maintenance ensures optimal performance and longevity.

After Each Use: Clean underside of deck (mower off, battery removed). Wipe exterior with dry cloth.
Blade Care: Inspect blade monthly for damage or dullness. Sharpen or replace as needed (use blade removal tool).
Wheel Care: Check wheels for free movement; clean axle if necessary.
Storage: Fold handles, remove battery, store in dry location. Charge battery every 3 months during storage.

CAUTION! Always disconnect battery before performing any maintenance. Wear gloves when handling blade.

Safety Information

Read all instructions before use. Keep bystanders and pets away. Wear sturdy shoes and eye protection. Do not mow on steep slopes. Never operate without grass bag, mulching plug, or discharge chute properly installed. Do not use in rain or on wet grass. Keep hands and feet away from moving parts. The blade continues to rotate after turn-off; wait for complete stop.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Mower won't start	Safety key not inserted; dead battery; safety handle not engaged	Insert safety key; charge battery; grip safety handle fully.
Poor cutting performance	Dull blade; wet grass; cutting height too low	Sharpen/replace blade; mow when dry; raise cutting height.
Battery drains quickly	Old battery; thick/wet grass; extreme temperatures	Check battery health; mow more frequently; avoid extreme conditions.
Uneven cut	Uneven tire pressure; deck not level; dull blade	Check tires; level deck; sharpen blade.
Excessive vibration	Damaged blade; debris in deck; loose parts	Inspect and replace blade; clean deck; tighten all bolts.

Reset: Remove battery for 30 seconds to reset electronics.

Service: 1-800-4-DeWalt (1-800-433-9258); www.dewalt.com