Immediately after using the battery pack, the Fuel
Gauge may display a lower charge than it will if
checked a few minutes later. The battery cells "re-
cover" some of their charge after resting.
Under extreme circumstances, the internal tem-
perature of the battery could become too high. If
this happens, the fuel gauge lights will flash in an
alternating pattern and the product will not run. Allow
the battery to cool down.
Fuel Gauge
Lights
Diagnosis
Solution
Lights 1 - 4
Remaining
Continue working.
Solid
run time
1 Light,
Less than
Prepare to charge
flashing
10% run
pack.
slowly
time left
1 Light,
End of
Charge pack.
flashing
discharge
quickly
Lights 1-4,
Current
Release trigger.
flashing
draw too
Once fuel gauge
quickly
high
has stopped
flashing, restart and
reduce pressure.
Lights 1&3 /
Battery
Release trigger and
2&4, flashing
temperature
allow battery to cool.
alternatingly
too high
Lights 1&4 /
Communi-
Remove the battery.
2&3, flashing
cation error
Press the Fuel
alternatingly
Gauge button to
clear. Reinsert the
battery.
†
If the problem persists, take the product, charger, and battery pack
†
to a MILWAUKEE service facility.
Battery Pack Protection
To protect itself from damage and extend its life,
the battery pack's intelligent circuit monitors current
draw and temperature. In extremely high torque,
binding, stalling, and short circuit situations, the
battery pack will turn OFF the product if the current
draw becomes too high. The fuel gauge will flash.
Release the trigger, wait for the fuel gauge to stop
flashing, and then restart.
Cold Weather Operation
MILWAUKEE Li-Ion battery packs are designed to
operate in temperatures below freezing. When the
battery pack is too cold, it may need to warm up
before normal use. Put the battery on a product and
use the product in a light application.
Transport
The regulations pertaining to the transport of Li-ion
batteries are affected by whether the battery is trans-
ported in a personal vehicle or offered for shipment
via a commercial carrier. Always ship Li-Ion batteries
in accordance with the current regulations governing
the chosen mode of transport (e.g. ground, air, sea).
When in doubt, contact MILWAUKEE, the carrier
or other trained Dangerous Goods professional to
determine applicable regulations. The personal trans-
port of Li-Ion battery packs is allowed when done in
accordance with these warnings and instructions.
When shipping Li-ion batteries with a commercial
carrier, they are shipped under classification UN 3480
(battery only) or UN 3481 (batteries contained in
or packed with equipment). The proper packaging,
labeling, marking, and documentation requirements
are generally dependent upon whether the particular
batteries are rated greater than or less than 100 Wh.
Often, Li-Ion batteries rated 100 Wh or less are
"excepted" from certain shipping regulations. In the
U.S., products shipped via ground transport may be
"excepted" from certain hazardous material shipping
regulations if they are under 300Wh.
Battery packs MXFXC608 and MXFHD812 are
above 300Wh and will need to be shipped to DG-9
regulations.
To ensure the MXFXC406 battery is below 300Wh
during transport, the shipping switch must be in the
locked position:
UNLOCK
LOCK
1. Pull out the shipping switch tab.
2. Install the shipping cap provide with the battery
at time of purchase, or secure a cable tie through
the hole in the shipping switch tab.
To reduce the risk of injury or ex-
WARNING
plosion, never burn or incinerate a
battery pack even if it is damaged, dead or com-
pletely discharged. When burned, toxic fumes
and materials are created.
Disposing of MILWAUKEE Li-Ion
Battery Packs
MILWAUKEE Li-Ion battery packs are more envi-
ronmentally friendly than some other types of power
tool battery packs (e.g., nickel-cadmium). Always
dispose of battery packs according to federal, state
and local regulations. Contact a recycling agency for
recycling locations.
Even discharged battery packs contain some energy.
Before disposing, use electrical tape to cover the
terminals to prevent the battery pack from shorting,
which could cause a fire or explosion.
RBRC Battery Recycling Seals
The RBRC™ Battery Recycling Seals (see the
Symbology section) on a battery packs indicates that
MILWAUKEE has arranged for recycling with the Re-
chargeable Battery Recycling Corporation (RBRC).
At the end of its useful life, return the battery pack
to a MILWAUKEE Branch Office/Service Center or a
participating retailer. For more information, visit the
RBRC web site at www.rbrc.org.
Battery Packs with ONE-KEY™
To learn more about the ONE-KEY™ functionality,
go to milwaukeetool.com/One-Key. To download the
ONE-KEY™ app, visit the App Store or Google Play
from your smart device.
ONE-KEY™ Indicator
Solid Blue
Wireless mode is active and ready
to be configured via the ONE-KEY™
app.
Blinking Blue Machine is actively communicating
with the ONE-KEY™ app.
Blinking Red Machine is in security lockout and
can be unlocked by the owner via
the ONE-KEY™ app.
4
MX FUEL™ LI-ION
CHARGERS
Charge only MILWAUKEE M X
WARNING
FUEL™Li-Ion batteries in this
MILWAUKEE Li-Ion charger. Other types of bat-
teries may cause personal injury and damage.
When to Charge the Battery Pack
with this MILWAUKEE Charger
Remove the battery pack from the tool for charg-
ing when convenient. MILWAUKEE batteries do
not develop a "memory" when charged after only
a partial discharge. It is not necessary to run down
the battery pack before placing it on the charger.
• U se the Fuel Gauge to determine when to charge
your MILWAUKEE Li-Ion battery pack.
• Y ou can "Top-Off" your battery pack's charge before
starting a big job or long day of use.
• T he only time it is necessary to charge the
MILWAUKEE Li-Ion battery pack is when the battery
pack has reached the end of its charge. To signal
the end of charge, power to the tool will drop quickly,
allowing enough power to finish making a cut, drilling
a hole, or driving a fastener. Charge the battery pack
as needed.
How to Charge the Battery Pack
Align the battery pack with the bay and slide the bat-
tery pack into the charger as far as possible. The Cool
Cycle fans will turn on. The red light will come on,
either flashing quickly (battery pack or charger is too
hot or cold), flashing slowly (communication between
pack and charger) or continuous (pack is charging).
• A fully discharged battery pack with an internal tem-
perature in the normal range will charge in about 35
to 75 minutes, depending on the battery pack and
internal temperature of the charger.
• H eavily cycled batteries may take longer to charge
completely.
• T he fuel gauge lights are displayed as the pack is be-
ing charged, indicating how fully charged the pack is.
The fuel gauge will turn off when charging is complete.
• A fter charging is complete, the continuous green
light will come on.
• I f the light indicator flashes red and green, check that
the battery pack is fully seated into the bay. Remove
the battery pack and reinsert. If the light continues
to flash red and green, remove pack(s) and unplug
charger for at least 2 minutes. After 2 minutes, plug
charger back in and insert pack. If the problem
persists, contact a MILWAUKEE service facility.
• I f the light indicator does not come on, check that
the battery pack is fully seated into the bay. Remove
the battery pack and reinsert. If the light indicator
still does not come on, remove pack(s) and unplug
charger for at least 2 minutes. After 2 minutes,
plug charger back in and insert pack. If after these
attempts the light indicator still does not come on,
contact a MILWAUKEE service facility.
• I f the light indicator double blinks red slowly (while
no pack is inserted), one or more fans are damaged.
The battery pack will not cool while charging, and will
charge at a reduced rate. Contact a MILWAUKEE
service facility.
ONE-KEY™ Charger Indicators
To learn more about the ONE-KEY™ functionality,
go to milwaukeetool.com/One-Key. To download the
ONE-KEY™ app, visit the App Store or Google Play
from your smart device.
ONE-KEY™ Indicator
Solid Blue,
Wireless mode is turning on.
Then Fadeout
Blinking Blue
Machine is actively communicating
(Even)
with the ONE-KEY™ app.
Blinking Blue
Machine is actively transmitting
(Uneven)
data to the ONE-KEY™ app.
Blinking Red
Machine is in security lockout and
can be unlocked by the owner via
the ONE-KEY™ app.
Charging a Hot or Cold Battery Pack
The fast Red Flashing Indicator light on the charger
indicates that the battery pack or charger temperature
is outside the charging range. Once the battery pack
or charger is within the acceptable range, normal
charging will take place and the red light will be contin-
uous. Hot or cold batteries may take longer to charge.
Battery Pack
or Charger
Red Charger
Charging
Temperature
Indicator Light
Status
Too Hot
Fast Flashing
Not charging
Normal Range Continuous
Normal charging
Too Cold
Fast Flashing
Not chargin
Powering the Charger with an Inverter
or Generator
The charger will operate with most 120 V generators
and inverters rated at 1,500 Watts or higher.
MAINTENANCE
ONE-KEY™
Chemical Burn Hazard.
WARNING
This device contains a
lithium button/coin cell battery. A new
or used battery can cause severe in-
ternal burns and lead to death in as
little as 2 hours if swallowed or enters the body.
Always secure the battery cover. If it does not
close securely, stop using the device, remove the
batteries, and keep it away from children. If you
think batteries may have been swallowed or en-
tered the body, seek immediate medical attention.
Internal Coin Cell Battery
An internal coin cell battery is used to facilitate full
ONE-KEY™ functionality.
To replace the battery:
1. Remove the battery pack.
2. Remove the screw(s) and open the coin cell bat-
tery door.
3. Remove the old coin cell battery, keep it away from
children, and dispose of it properly.
4. Insert the new coin cell battery (3V CR2032), with
the positive side facing up.
5. Close the battery door and tighten the screw(s)
securely.
5
g