Mitsubishi Electronics MSZ-FA35VA, MSZ-FA25VA service manual Indoor electronic control P.C.Board

The unit does not operate with the remote controller.

Also, POWER lamp does not light up by pressing EMERGENCY OPERATION switch.

C Check of indoor electronic control P.C. board and indoor fan motor

Turn OFF the power supply.

Remove indoor fan motor connector CN211, vane motor connector CN151 front panel driving motor connector connector CN1U1 and i-see Sensor motor connector CN110 from the indoor electronic

control P.C. board and turn ON the power supply.

Does the unit operate with the remote controller?	Yes
Does POWER lamp light up by pressing EMERGENCY
OPERATION switch?
No

Turn OFF the power supply.

Check both “parts side” and “pattern side” of the indoor electronic control P.C. board visually.

Measure the resistance of the front panel driving motor coil.

Normal value is approx. 100'

Measure the resistance of i-see Sensor motor coil.

Normal value is approx. 300'

Measure the resistance between CN211 3 and 4 of the indoor fan motor connector. Normal value is approx. 30k' to 50k'.

Measure the resistance of the horizontal vane motor coil and the vertical vane motor coil. Normal value is approx. 300' or 250'.

Replace the varistor(NR11) and fuse(F11).

Yes

Are the varistor(NR11) burnt No and the fuse(F11) blown?

Be sure to check both the fuse and the varistor in any case.

No

Is the fuse(F11) blown only?

Short circuit:

Replace the front panel driving motor and the indoor electronic control P.C. board.

Short circuit:

Replace i-see Sensor motor and the indoor electronic control P.C. board.

Short circuit:

Replace the indoor fan motor.

Short circuit:

Replace the horizontal vane motor, the vertical vane motor and the indoor electronic control P.C. board.

w1,2 Yes

	Measure the resistance between
	1(+) and 3(-) of the indoor fan
	motor connector (to CN211 on the
	indoor electronic control P.C. board) .
w3. Short circuit:		w3	No
		Is the resistance 1M'
The indoor fan motor is

abnormal.	or more?
	Yes
	Replace the fuse (F11).

w1. The fan motor connector's1 lead wire is red, whereas 3 is black.

w2. Connect "+" of the tester to fan motor connector's1 lead wire, and "-" to 3 lead wire, otherwise the resistance cannot be measured properly.

Replace the fuse (F11) and the indoor fan motor.

Measure the cement resistance R111 on the indoor electronic control P.C. board.

Is the resistance approx. 4'?

No

Replace the indoor electronic control P.C. board and the indoor fan motor.

Indoor electronic control P.C.Board

CN211

Yes

Replace the indoor electronic control P.C. board.

Varistor(NR11)

CN201

Fuse(F11)

23