Daikin FDMQ12RVJU, Service Manual

Page: 183 / 242

SiUS091601EA Troubleshooting for Outdoor Unit
Part 6 Service Diagnosis 178
7.15 Output Overcurrent Detection
Error Code
L5
Method of Error
Detection
An output overcurrent is detected by checking the current that flows in the inverter DC section.
Error Decision
Conditions
 A position signal error occurs while the compressor is running.
 A rotation speed error occurs while the compressor is running.
 An output overcurrent signal is fed from the output overcurrent detection circuit to the
microcomputer.
 If the error repeats, the system is shut down.

Reset condition: Continuous run for about 11 minutes without any other error
Supposed
Causes
 Poor installation condition

Closed stop valve
 Defective power module
 Wrong internal wiring
 Abnormal power supply voltage

Defective outdoor unit PCB
 Power supply voltage out of specification
 Defective compressor
Troubleshooting
(R24911)
Caution
NO
YES
NO
YES
*
An output overcurrent may result from wrong internal wiring. If the system is interrupted by an output
overcurrent after the wires have been disconnected and reconnected for part replacement, check the
wiring again.
Check No. 17
Check No.15
Turn off the power and disconnect
the harnesses U, V, and W.
Turn off the power. Then, turn on
the power to restart the system.
See if the same error occurs.
Monitor the power supply voltage,
discharge and suction pressures,
and other factors for a long term.
Possible causes
*
Momentary drop of power supply
voltage
*
Compressor overload
*
Short circuit
Check the installation condition.
Check with the inverter analyzer.
Not a malfunction.
Keep observing.
Check the connectors and
other components.
Fully open the stop valve.
Error again?
Stop valve fully open?
*
Inverter analyzer:
RSUK0917C
Be sure to turn off the power switch before connecting or disconnecting
connectors, or parts may be damaged.
A Go to the next page