Toshiba RAS-M18EAV-E How to Check Simply the Main Parts, How to Check the P.C. Board Indoor Unit

Diagnosis/Process flowchart					Item	Contents	Summary
A				B	Check	Check winding resistance
						between phases of compres-
						sor, and resistance between
						outdoor frames by using a
						tester.	→ OK if 10MΩ or more
						• Is not grounded.
			Replace control
			board assembly.			• Is not short-circuited	 → OK if 0.51Ω → 0.57Ω
						between windings.	
						• Winding is not opened.	 (Check by a digital tester.)
Check
		NG
compressor
winding
resistance.					Operation	Remove connector CN300 of
	OK					the outdoor fan motor, turn
						on the power supply breaker,
Replace				Replace		and perform the operation.
						(Stops though activation is
control board.				compressor.
						prompted.)

Check operation within 2 minutes 20 seconds after activation stopped.

11-9. How to Check Simply the Main Parts

11-9-1. How to Check the P.C. Board (Indoor Unit)

(1)Operating precautions

1)When removing the front panel or the P.C. board, be sure to shut off the power supply breaker.

2)When removing the P.C. board, hold the edge of the P.C. board and do not apply force to the parts.

3)When connecting or disconnecting the connectors on the P.C. board, hold the whole housing. Do not pull at the lead wire.

(2)Inspection procedures

1)When a P.C. board is judged to be defective, check for disconnection, burning, or discolora- tion of the copper foil pattern on this P.C. board.

2)The P.C. board consists of the following 2 parts

a.Main P.C. board part :

DC power supply circuit (5V, 12V, 15V), Indoor fan motor control circuit, CPU and peripheral circuits, buzzer, and Driving circuit of louver.

b.Indication unit of infrared ray receiving Infrared ray receiving circuit, LED :

To check defect of the P.C. board, follow the procedure described below.

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