Carrier 38MBRCQ36AA3 - Diagnosis and Solution (Communication); EL 01: Indoor;Outdoor Communication Error

38MBRC: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
18
DIAGNOSIS AND SOLUTION
EL 01 (Indoor and Outdoor Unit Communication Error Diagnosis and Solution)
Description: Indoor unit can not communicate with outdoor unit
Recommended parts to prepare:
• Signal wires
• Magnet ring
• Indoor PCB
• Outdoor PCB
Troubleshooting and repair:
XYE Communication:
No
,
Power o

, then restart the unit 2
minutes later.
/
.
Adopt shield cable /Shield cable
earthing.
No
Yes
Correct the connection.
No
Yes
or
Remove interference or
add magnet ring on power
wire
Yes
Yes
Replace the signal wire.
Yes
Pull out and re-insert.
No
No
Replace the main PCB.
Is the error solved?
Yes
Replace the outdoor main PCB.
No
.
?
Check whether there’s any
interference.
Such as too many lamps , power
transformers. Or the signal wire
is too long .
Check whether the signal wire is
shield cable or whether the
shield cable is earthing .
Check whether the wire has the
correct polarity. P to P, Q to Q , E
to E.
Check whether the signal wire is broke.
Check whether the signal wires
are well placed on the PCB.