Skil BY8708C-01 Guide D'utilisation page 16

NOTICE: If the battery pack cannot accept a charge, the contacts
of the charger or battery pack may be contaminated. Clean the
contacts of the charger or battery pack (e.g., by inserting and
removing the battery several times or by cleaning with a cotton
swab and alcohol), or replace the battery pack, as required.
To Attach and Detach Battery Pack
Follow the instructions in the Owner's Manual for the individual SKIL
tool.
Faulty Battery Pack
If the charger detects a problem, the red Error Indicator will begin
flashing. Remove and re-insert the battery pack in the charger. If the
Error Indicator flashes a second time, try charging a different battery
pack.
a. If a different battery pack charges normally, have the first faulty
battery pack serviced by an Authorized SKIL Service Station.
b. If a different battery pack also indicates an error, the charger
may be faulty. Have the charger serviced by an Authorized SKIL
Service Station.
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