Toshiba MMU-AP0091H service manual Diagnosis Procedure for Each Check Code, 138

9-5. Diagnosis Procedure for Each Check Code

Check code	Check code name		Cause of operation
[E01] / [–]	Communication error between	1. Remote controller interconnecting cable
(TCC-L / AI-NET)	indoor and remote controller		error
	(Detected at remote controller side)	2. Indoor power supply error
		3.	Indoor P.C. board error
		4.	Remote controller address setup error
		5.	Remote controller P.C. board error

Check code	Check code name	Cause of operation
[E03] / [97]	Communication error between	No communication from remote controller and
(TCC-L / AI-NET)	indoor and remote controller	communication adaptor
	(Detected at indoor side)

This error is detected when the indoor unit cannot receive a signal from the remote controller. Check communication wiring of the remote controllers A and B.

As communication is impossible, this fault code [E03] is not displayed on the main remote controller. It is displayed on TCC-LINK central controller.

Is the interconnection cable of		NO
remote controllers (A/B) normal?
	YES
Is there no disconnection or		YES
connector contact error on harness out
of terminal block of indoor unit?
	NO

NO

Is a group control operation?

YES

Correct interconnection cable of remote controller.

Correct connection and check circuit cabling.

Check code	Check code name		Cause of operation
[E04] / [04]	Indoor/Outdoor	1.	Power of outdoor unit was firstly turned on.
(TCC-L / AI-NET)	communication circuit error	2.	Connection error of communication line
	(Detected at indoor side)		between indoor and outdoor
		3.	Terminal resistance setup error on outdoor
			header unit.
		4.	Address setup error

Is power of each indoor unit turned on?

NO

Check power connection status of indoor unit. (Turn on power again.)

Was power turned on in order	NO
of indoor unit Æoutdoor unit?

Turn on power again in order of indoor unit Æoutdoor unit.

138

	YES
Is power applied to remote controller?		NO
AB terminals: Approx. DC18V
	YES

Check indoor P.C. board.

Defect ÆReplace

	YES
		NO
Is connection (U1/U2 terminals) of
indoor/outdoor interconnection cable normal?

Correct interconnection cable.

Are two remote controllers used YES

Change one to main/other to sub.

YES

without the correct identification?

NO

(Remote controller address connector)

Check remote controller P.C. board.

Defect ÆReplace

Is the end terminal resistance		NO
setup of outdoor unit normal?
	YES
		NO
Is address setup correct?
	YES

Correct the end terminal resistance setup.

Set up address again.

Check code Check code name Cause of operation

[E02] / [–]	Remote controller sending error Signal could not be sent to indoor unit.
(TCC-L / AI-NET)	Check the communication wire of the remote
	controller.

* It is not displayed on 7-segment display of the central control controller.

Is power applied to fuse (F03)		NO
on indoor P.C. board?
	YES
		YES
Is there no noise, etc?
	NO

Check connection of interconnection cable between indoor and outdoor is correct, and then connect communication line connector on indoor P.C. board (CN40) to CN44 (EMG).

Check noise etc. and eliminate it if any.

Is communication wiring between		NO
remote controller and indoor unit correct?
	YES

ÆSending circuit error of the remote controller Replace remote controller.

Correct the communication wiring.

Check indoor P.C. board.

Defect ÆReplace

For details, refer to “Troubleshooting in test operation”.