LG AP-Z Series Service Manual page 40

Electronic Parts Troubleshooting Guide
3) No heater operation works
Is the heating operating?
YES
Is the Compressor
operating?
YES
Is the Heat S/W of Main
PCB "ON"?
YES
Is the heater S/W of Main
PCB"ON"?
YES
Is the DC 5V at 15 pin of
MICOM
YES
Is the DC 12V
at eack terminal? (RY-HEATER
COIL)
YES
Is the
AC220V (AC 240 V) between
connector(HEATER) and CN-outunit of
Main P.C.B
YES
Check the heater wiring
40 Floor Standing Type Air Conditioner
NO
NO
NO
NO
NO
NO
NO
Select the heating operation mode.
Compressor "ON"
Heat S/W "ON"
Heater S/W "ON"
Replacement MICOM
Replacement IC02M
Replacement RY-HEATER