Carrier 40MBDAQ - Page 39

40MBDAQ: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
39
DIAGNOSIS AND SOLUTION (CONT.)
J3 (PFC module protection)
Description: When the voltage signal that the IPM sends to the compressor drive chip is abnormal, the display LED displays
“J3” and the air conditioner turns off.
Recommended parts to prepare:
• Wiring
• IPM board
• Outdoor fan assembly
• Compressor
• Outdoor PCB
Troubleshooting
PFC module protection
Check whether
the connecting line between the
main board and the PFC module
is connected tightly.
Tighten the
connection and check
if the unit functions
normally.
NO
Measure the voltage
between P and N.
YES
Is it normal? Replace the outdoor main board.YES
Check the PFC module inductance.
If the inductance is good,
the resistance of the two ports is 0.
NO
Is it good?
Replace the inductance.NO
Replace the PFC module.
YES
NO
Problem solved.