Hitachi UC 18YML2 Technical Data And Service Manual page 17

(2) Trouble mode (B)
Red pilot lamp does not stay lit
(continues to flash) after battery
has been connected.
Are the connection terminals of the
charger or battery dirty, deformed,
or otherwise abnormal?
Check with tester.
Is the resistance between
(LS) and (-) terminals
2 KΩ to 100 KΩ?
Faulty internal circuits
Replace the PCB.
YES
NO
NO
YES
-15-
Remove dirt or
correct abnormality.
Replace the battery.