Mitsubishi Electric LGH-250RVXT-E Handbook page 30

Error LED1 LED2
Code (green) (red)
5101 4 Outdoor air
blinks (OA) thermis-
tor related
error
5102 5 Indoor air (RA)
blinks thermistor
related error
6600 6 Multiple ad-
blinks dress error
6602 2 Transmission
blinks error
(transmission
processor
hardware er-
ror)
*1 This refers to devices assigned an address number in MELANS such as the Lossnay unit, City Multi indoor
unit, City Multi outdoor unit, or system controller.
Symptom
Faulty connection of the thermis-
tor connector (CN22) on the control
circuit board
Thermistor failure
Faulty connection of the thermistor
connector (CN5) on the control circuit
board
Thermistor failure
The system contains two or more
units (*1) set with the same address
in the same M-NET transmission
cable line.
Faulty connection of the M-NET
transmission cable
Wiring was performed with power
•
still supplied to the M-NET transmis-
sion cable.
Accidental communication error
•
Power is supplied to the same trans-
mission cable from two or more
power supply units.
The power supply unit is connected
to the TB3 terminal of the transmis-
sion booster.
PZ-61DR-E is connected to the ter-
minals (TB5 [A] [B]).
Malfunction of the unit (*1) where an
error occurs
Cause
─ 30 ─
Corrective action
Check the connector (CN22) con-
nection.
Disconnect the connector (CN22),
and check the resistance of the
thermistor.
If the equivalent thermistor resist-
ance differs greatly from the am-
bient temperatures, replace the
thermistor. (See (6) Temperatures
and thermistor resistance table
(page 34).)
Check the connector (CN5) con-
nection.
Disconnect the connector (CN5),
and check the resistance of the
thermistor.
If the equivalent thermistor resist-
ance differs greatly from the am-
bient temperatures, replace the
thermistor. (See (6) Temperatures
and thermistor resistance table
(page 34).)
Find the units (*1) set with the
same address, and set unique ad-
dresses to these units.
Check the items described in (1)
2.
Restart the system after complet-
ing wiring.
If the error re-occurs, check for
noise on the transmission cable.
If the above does not correct the
problem, replace the control circuit
board of the Lossnay unit.
Check the wiring of the power
supply unit and the transmission
booster.
Connect PZ-61DR-E to the ter-
minals (TM4 1 2). (See the
Lossnay technical manual.)
Check the unit (*1) where the error
occurs.