Communication Malfunction E6 - Carrier 38GRQB12-3 Service Manual

5. Communication Malfunction E6

with display board? Main board of
Communication wire is damaged?
Start
Cut off power supply. Check if
connection line of IDU and ODU
and the wire inside electric box
are correctly connected.
Correct connection? No
Yes
Main board matches
IDU matches with that of ODU?
Yes
No
Replace IDU's
main board
Malfunction eliminated?
Yes
End
Fig. 29 – Troubleshooting
Connect the line
according to
wiring diagram.
No
Match correctly
no
according to product
specification
No
Replace
Yes
communication
cord
No
Replace ODU's
No
main board.
26
Malfunction eliminated?
Malfunction eliminated?
Yes
Malfunction eliminated? Yes
Yes