Carrier 38MBQ Series Service Manual page 31

DIAGNOSIS AND SOLUTION (CONT)
Table 25—High Temperature Protection of Compressor Top Diagnosis and Solution (P2)
Error Code
Malfunction Decision Conditions
Supposed Causes
Troubleshooting
Check the air flow system
of the indoor and outdoor units
Does a problem exist?
No
Power off and then restart the unit
10 minutes afterwards
Yes
Check compressor
temperature. Is it within
acceptable parameters?
Yes
Check the refrigerant
system. Is it functioning
properly?
Yes
P2
If the sampling voltage is not 5V, the LED displays the failure.
S
Power supply problems
S
System leakage or block
S
PCB faulty
Clear up the air inlet and outlet or the heat
. Yes
exchanger of the indoor and outdoor units.
Check the overload
No protector. Is it properly
Measure the resistance
between the two ports of
the OLP. Is it zero?
Replace the outdoor control PCB
No
wired?
Yes
No
Yes
31
Ensure a proper
connection
Replace the OLP