DOWNLOAD Panasonic U-4LE1E5 / U-4LE1E8 / U-5LE1E5 / U-5LE1E8 / U-6LE1E5 / U-6LE1E8 Service Manual ↓ Size: 7.25 MB | Pages: 127 in PDF or view online for FREE

3-49

Abnormal current is detected at DCCT before start-up.

Open-wire of compressor and/or backspin detected.

•

Start-up failed during overcurrent and/or step-out detected.

•

•

Secondary current is not detected during INV compressor is running.

•

1-1

1-2

2-1

Yes

No

1 Wiring

Correct wiring 
connections

1-2

Disconnected parts, miswiring and/or poor connections (loose) 
are observed in the connections of outdoor board(s) that are 
connected by wiring from the HIC PC board. *1

Yes

No

Correct wiring 
connections

Disconnected parts, miswiring and/or poor connections (loose) 
are observed in the connections of HIC PC board(s) that are 
connected by wiring to a compressor. *1

2-1

2-2

3-1

Yes

No

2

Compressor
wiring

Correct

2-2

Conditions such as burned terminal covers and/or discolored 
terminals are observed at the connectors of the compressor 
terminals. *1

Yes

No

Eliminate looseness
by changing the
terminals, or crimping
the terminals again.

Disconnections and/or miswiring is observed in the connections 
of the compressor terminals. *1

4

4-1

Check the
outdoor 
control PC 
board

Replace the control PC board and operate the unit.

3-1

3-2

4-1

Yes

No

3 Check the

HIC PC
boards

Replace the HIC board

3-2

Replace the HIC PC board and operate the unit. (Apply putty 
and screws must not be loose) Does it operate normally?

Yes

No

See what happens.

See what happens.

The results of the pass/fail tests for the following HIC PC board 
IPM show it to be outside the range of the resistance of a 
conforming part.

Checking for looseness of compressor terminals by wiggling them has the adverse effect of loosening them, so do not do it.
Evaluate them by discoloration of wire insulation near the terminal.

*1 

Measure with an analog tester. (Set to the k ohm range)

•

Measure the board by itself. (Remove wires connected from other parts.)

•

Measure using IPM terminals.

•

Excepting the parts of “
value is “0 = short-circuit”.

”, it is acceptable if a small resistance value appears as a reference value unless the 

•

Tester terminals

-

Resistance value (ohm)

U

1 k to 5 k

V

1 k to 5 k

W

1 k to 5 k

U

1 k to 5 k

V

1 k to 5 k

W

1 k to 5 k

NU

5 k to 10 k

U

100 k to   

V

100 k to   

W

100 k to   

P

100 k to   

P

NU

+

Tester terminals

+

Resistance value (ohm)

P

NU

-

U

100 k to   

100 k to   

V

100 k to   

W

100 k to   

SM830196-03_Mini_VRF SYS.indb   49

SM830196-03_Mini_VRF SYS.indb   49

2014/09/08   10:55:03

2014/09/08   10:55:03

3-50

NU

W

V

U

P

NU

W

V

U

P

CN-VDC+

CN-VDC-

4WAY Valve

(CN-20S)

Crankcase 

heater

(CN-CH)

4WAY Valve

(CN-20S)

Crankcase 

heater

(CN-CH)

PIN1

(VDC+)

PIN2

(VDC-)

SM830196-03_Mini_VRF SYS.indb   50

SM830196-03_Mini_VRF SYS.indb   50

2014/09/08   10:55:04

2014/09/08   10:55:04

3-51

(1)

(2)

(1)

(2)

(3)

(4)

(5)

(6)

(7)

(8)

(9)

(10)

(11)

(12)

Electronic control valve (MOV1)

Crankcase heater

MOV1:  Measure the voltage between plug pin 5 and pins 1 through 4 at the CN-MOV1 connector (5P, white) 
on the outdoor unit control PCB. (Because of the pulse output, a simplified measurement method is used. 
Set the tester to the 12 V range; if the value displayed is approximately 4 V, then the voltage is normal.)

If the voltage is normal, measure the resistance between connector pin 5 and pins 1 through 4. 

Resistance between pin 5 and pins 1 through 4 should be approximately 46    for all. (If the result is 0
or,      then replace the coil.)

Connect a clamp meter to 1 of the 2 crankcase heater wires and measure the current. The current is 
normal if the result is 0.15 A or higher. 
(As a guide, the current should be 0.14 A (180 V) – 0.17 A (220 V).)

When the test pin on the outdoor unit main control PCB is short-circuited, each part can be operated individually.
After turning OFF the outdoor unit power, short circuit the test pin (CN-TEST, black), then turn the power back ON. 

The following operations will start after turning ON the outdoor unit power when the test pin (CN-TEST, black) is 
short-circuited.

Set DC fan motor at W5 (FM1 : 340 – 360 rpm, FM2 : 360 – 380 rpm).

20S turns ON for 0.5 second.

Check Inter-unit control wiring circuit.
If normal state, go to the next step. If not, it stops after LED1 starts blinking at 0.5 second intervals and LED2
turns off.

Connector CH1 turns ON for 0.5 second.

Do the test to read / write EEPROM.
If normal state, go to the next step. If not, it stops after LED1 starts blinking at 0.5 second intervals and LED2
lights.

Connector O

2

turns ON for 0.5 second.

Check inter-outdoor unit control wiring circuit to outdoor unit maintenance remote controller.
If normal state, go to the next step. If not, it stops after LED1 turns off and LED2 starts blinking at 0.5 second
intervals.

LED1 turns ON for 0.5 second.

Do the test(1) of circuit for writing micro-computing software.
If normal state, go to the next step. If not, it stops after LED1 starts blinking and LED2 starts blinking at 0.5
second intervals.

LED2 turns ON for 0.5 second.

Do the test(2) of circuit for writing micro-computing software.
If normal state, go to the next step. If not, it stops after LED1 starts blinking and LED2 starts blinking at 0.5
second intervals.

Outputs listed below turn ON for 0.5 second.

1

2

3

4

5

MOV1 – A

MOV1 – B

MOV1 – / A

MOV1 – / B

SM830195-00.indb   52

2011/09/30   15:41:52

SM830196-03_Mini_VRF SYS.indb   51

SM830196-03_Mini_VRF SYS.indb   51

2014/09/08   10:55:05

2014/09/08   10:55:05

3-52

1-1

Adjust setting 
temperature

1-2

Yes

No

Connect correctly

1-3

Yes

No

1

Check if the sensors are connected correctly.
Are all connection made properly? 
Room temp. (TA) in yellow, heat exchanger (E1) in red, 
heat exchanger (E2) in black, heat exchanger (E3) in brown, 
air outlet (BL) in green

1-2

Indoor control 
PC board

Abnormality does not occur. Protective function can be checked when the outdoor maintenance remote controller is 
connected.

•

Setting temperature reaches the level set ON thermostat. 
Setting temperature is too low in heating mode and too high 
in cooling and dry mode.

2

DISP (display mode) is applied.

With a thermostat OFF in heating mode, wind speed 
(item code 05) is out of range 0 - 6. (Use Simple Setting 
Function on standard timer remote controller.)

1-3

1-4

1-5 EXCT(demand control) is applied.

Outdoor 
control 
PC board

3 Control 

equipment

4 System

Turn OFF(OPEN)

1-4

Yes

No

Choose one of 0 to 6

1-5

Yes

No

Turn OFF(OPEN)

2-1

Yes

No

2-1

Outdoor unit and protective function of a system are operating.
(Connect outdoor maintenance remote controller to RC socket 
on outdoor unit main control PC board and check alarm 
messages.)

See operational status

2-2

Yes

No

2-2

Discharge temperature is over 80°C in stop mode and does not 
decrease. (Connect outdoor maintenance remote controller to 
RC socket on outdoor unit main control PC board and check 
alarm messages.)

Replace discharge 
temperature sensor

2-3

Yes

No

2-3

Demand value always stays low. (The value is lower than 70. 
Excluding -1 (unlimited))(Connect outdoor maintenance remote 
controller to RC socket on outdoor unit main control PC board 
and check alarm messages.)

Increase values 
(over 70

）

2-4

Yes

No

2-4 DEMAND or EXCT(demand control) is applied.

Turn OFF(OPEN)

3-1

Yes

No

3-1

Demand setting is made by control units (P-AIMS, Seri-Para I/O 
unit for outdoor unit, Seri-Para I/O each indoor unit.)

Turn OFF

4-1

Yes

No

4-1

When operating in cooling (including auto cooling & heating) 
and dry mode, lowest temp. of indoor E1, E2 and E3 sensor is 
less than 2°C (under anti-freeze control).

Wait until more than 
2°C reaches

4-2

Yes

No

4-2 During defrosting operation

Wait for a few minutes 
to 10 minutes or so
4-3

Yes

No

4-3 Outdoor unit PC board failure → Replacement

According to the type of models, the indoor sensors will not be supplied in some cases.
According to the type of models, the outdoor DEMAND or EXCT will not be supplied in some cases.
When LINE Checker is used, the temperature sensors can be observed (display, record) simultaneously.
According to some areas, some of the models are unreleased.

SM830196-03_Mini_VRF SYS.indb   52

SM830196-03_Mini_VRF SYS.indb   52

2014/09/08   10:55:06

2014/09/08   10:55:06