Panasonic CZ-18BT1U, CS-MKE9NB4U, CU-4KE31NBU, CU-4KE24NBU Before the Operation, 3-1Condition: E01

(3) Serial Communication Error Identification Procedure

If the lamps on the main body show the following conditions after the completion of self-diagnostics, a communication error between the indoor unit and outdoor unit might be considered.

In such a case, identify the breakdown section by using the following procedure.

NOTE Refer to "Method of Self-Diagnostics" for the self-diagnostics procedure.

Lamp Operation Timer High Power

Condition

E01

E12

:Off

:Blinking

:Illuminated

< Before the Operation >

Warning

For terminal strip short circuit work or inter-unit wiring removal, turn off the power to avoid an electric shock.

Release the terminal strip short circuit after the completion of self-diagnostics.

Caution

Do not perform the short-circuit work between any other terminals except for specified ones on the specified terminal strip. If such work is performed between the incorrect terminals, the unit might be broken.

Prohibit

< Convenient Tool for Short-Circuit Work ( for example ) >	Cable	Alligator Clip
Alligator Clip

< Check Items before Troubleshooting Serial Communication Start >

After confirming that the following errors do not exist, start the "Troubleshooting Serial Communication" in "Condition: E01 and E12".

1.	Mis -wiring (inter-unit cable, etc.)	6.	Reactor failure (defective insulation, etc.)
2.	AC power failure	7.	High-Pressure Switch failure
3.	Blown fuse	8.	Overload Relay failure
4.	Power Relay failure	9.	Magnetic Coil failure (defective insulation, short-circuit, etc.)
5.	Outdoor Fan Motor failure (defective insulation, etc.)	10. Compressor failure (defective insulation, etc.)

(3-1) Condition: E01

Troubleshooting Serial Communication

Is the voltage of about DC12V

or more given between the terminals

2 and 3 on the outdoor unit terminal strip

(Serial Communication Line) ?

(Fig. 1)

Yes

A

( Continued to the next page A. )

		-			+												Outdoor Unit
					V
								Outdoor Unit				1	2		3		4	5	6
	1		2			3		4	5	6								Power
									Power			1	2		3
											Indoor Unit
	1		2			3								V
	Indoor Unit
													-	+
							Fig. 1									Fig. 2
No			1. Turn OFF the power and wait until the power lamp (LED)
				of the outdoor unit controller is turned OFF.
			2. Disconnect the cable from the terminal 3 on the indoor unit
				terminal strip.							(Fig. 2)
			3. Turn ON the power.

B

( Continued to the next page B. )

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