Fenix HM71R: How to Use, Charge & TroubleshootUpdated 5 days ago

How to operate, charge, and troubleshoot the Fenix HM71R. Key specs: 2,700 lumens max, 230 m beam, USB-C rechargeable 21700, IP68. For the full mode-by-mode output and runtime table, the downloadable reference manual, and current price, see the Fenix HM71R product page.

Operating Instructions

On/Off: press and hold the switch for 0.5 seconds to turn the lamp on or off.

Mode switching: with the lamp switched off, press and hold the switch for 0.5 seconds to enter Spotlight mode, and double click the switch to enter Floodlight mode. With the lamp switched on, press and hold the switch for 1.2 seconds to enter the other mode.

Output selection — Spotlight mode: single click the switch to cycle through Low→Med→High→Turbo.

Output selection — Floodlight mode: single click the switch to cycle through Red→Low→Med→High.

Lock/Unlock

Lock: with the lamp switched off, press and hold the switch for 3 seconds; the lamp will blink 4 times on Red mode to indicate locked status.

Unlock: with the lamp locked, press and hold the switch for 3 seconds; the lamp will activate with 4 one-second Red mode blinks and activate on Red mode. In locked status, clicking the switch will activate 4 one-second blinks on Red mode to indicate locked status.

Intelligent Memory Circuit

The headlamp memorizes the last selected output of Spotlight mode. When turned on again, the previously used output of Spotlight mode will be recalled. Each time Floodlight mode is entered, it starts on Red. If turning off the lamp in Turbo of Spotlight mode, when turned on again the High output level of Spotlight mode will always be recalled.

Battery Specifications

Fenix ARB-L21 Series (21700, 3.6V/3.7V): Recommended
Rechargeable Battery, Li-ion (21700, 3.7V): Usable
Rechargeable Battery, Li-ion (18650, 3.7V): Banned

21700 Li-ion batteries are powerful cells designed for commercial applications and must be treated with caution and handled with care. Only quality batteries with circuit protection will reduce the potential for combustion or explosion; cell damage or short circuiting are potential risks the user assumes.

Battery Replacement

Unscrew the cap to insert the battery with the anode side (+) toward the inside, then screw the cap back on.

Charging

Uncover the anti-dust cap and plug the USB Type-C side of the charging cable into the charging port of the lamp.
The normal charging time of the included Fenix ARB-L21-5000 V2.0 is about 4 hours (5V/2A) with the lamp switched off.
The indicator will display red while charging and turn green when fully charged.
Recharge a stored headlamp every four months to maintain optimal battery performance.
When charging, the Low output level of Spotlight mode can be used. The headlamp will not automatically power on after full charging.
When charging is complete, replace the anti-dust cap to ensure waterproof and dustproof ability.

Charging indication only works with a Fenix ARB-L21-5000 V2.0 battery.

Battery Level Indication

With the lamp switched off, single click the switch to check the battery status; the indicator will last for 3 seconds.

Green light on: saturated 100% - 80%
Green light flashes: sufficient 80% - 50%
Red light on: poor 50% - 20%
Red light flashes: critical 20% - 1%

Note: This only works with a Fenix ARB-L21-5000 V2.0 battery.

Intelligent Overheat Protection

The lamp will accumulate a lot of heat when used at relatively high output levels for extended periods. When the lamp reaches a temperature of 65°C or above, it will automatically step down a few lumens to reduce the temperature. When the temperature drops below 65°C, it will then allow the user to reselect the modes.

Low-Voltage Warning

When the voltage level drops below the preset level, the headlamp is programmed to downshift to a lower brightness level until Low output is reached. When this happens in Low output, the battery level indicator blinks to remind you to recharge or replace the battery. Note: this only works with a Fenix ARB-L21-5000 V2.0 battery.

Headband Assembly

The headband is factory assembled by default. Adjust the headband by sliding the buckle to the required length.

Troubleshooting

Lamp won't turn on, or blinks red 4 times when clicked: It is locked. With the lamp off, press and hold the switch for 3 seconds to unlock.
Lamp won't turn on at all: Recharge the battery and check it is inserted with the positive (+) end toward the inside. Only 21700 batteries fit; 18650 batteries are not allowed.
Flickers or turns on intermittently: Replace or recharge the battery, then clean the battery and lamp contacts with a cotton swab soaked in rubbing alcohol.
Brightness drops on its own during use: This is normal. The lamp steps down at 65°C to protect itself and lets you reselect modes once it cools. It also downshifts as the battery runs low.
Floodlight always starts on red: This is by design. Each time Floodlight mode is entered it starts on Red; single click to move to Low, Med and High.
Charging or battery indicator doesn't respond: The indicators only work with a Fenix ARB-L21-5000 V2.0 battery. Only Spotlight Low is available while charging.

If the above methods don't work, please contact Fenix Store support through live chat (the chat button on any page of fenix-store.com) or at [email protected].

Usage and Maintenance

Disassembling the sealed head can cause damage to the lamp and will void the warranty.
Fenix recommends using an excellent quality Fenix battery.
If the lamp will not be used for an extended period, remove the battery, or the lamp could be damaged by electrolyte leakage.
Loosen the cap or take out the battery to prevent accidental activation during storage or transportation.
Periodically clean the battery contacts with a cotton swab soaked in rubbing alcohol.

Warning

Do NOT place this headlamp within the reach of children!
Do NOT shine the headlamp directly into the eyes of anyone!
Do NOT shine flammable objects at close range, to avoid burning objects or causing danger due to high temperature!
Do NOT use the headlamp in inappropriate ways such as biting in the mouth, to avoid personal injury or life-threatening harm if the headlamp or internal battery fails!
This headlamp will accumulate a lot of heat while working, resulting in a high temperature of the headlamp shell. Pay attention to safe use to avoid scalding.
Turn off and lock the headlamp or remove the battery to prevent accidental activation when the headlamp is placed in a closed and flammable environment such as pockets and backpacks!
The LED of this headlamp is not replaceable; so the whole headlamp should be replaced when the LED reaches the end of its life.

What's Included

Fenix HM71R headlamp, ARB-L21-5000 V2.0 battery, USB Type-C charging cable, Spare O-ring, User manual, Warranty card.

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