Mitsubishi Electronics MUZ-GB50VA service manual Failure mode recall function, Off

10-2. Failure mode recall function

Outline of the function

This air conditioner can memorize the abnormal condition which has occurred once.

Even though LED indication listed on the troubleshooting check table (10-4.) disappears, the memorized failure details can be recalled.

This mode is very useful when the unit needs to be repaired for the abnormality which doesn't recur.

1. Flow chart of failure mode recall function for the indoor/outdoor unit

Operational procedure

The cause of abnormality cannot be found because the abnormality doesn't recur.

Setting up the failure mode recall function

Turn ON the power supply.

<Preparation of the remote controller>

1 While pressing both OPERATION SELECT

button and TOO COOL button on the remote controller at the same time, press RESET button.

2First, release RESET button.

And release the other two buttons after all LCD except the set temperature in operation display section of the remote controller is displayed after 3 seconds.

Press OPERATE/STOP(ON/OFF) button of the remote controller (the set temperature is displayed) with the remote controller headed towards the indoor unit. w1

Does the left lamp of OPERATION INDICATOR lamp on the indoor unit blink at the interval of 0.5 seconds?

Blinks: Either indoor or outdoor unit is abnormal. Beep are emitted at the same timing

as the blinking of the left lamp of OPERATION INDICATOR lamp. W2

No

(OFF)

W1. Regardless of normal or abnormal, a short beep is emitted once as the signal is received.

Indoor unit is normal.

But the outdoor unit might be abnormal because there are some abnormalities that can't be recalled with this way.

Confirm if outdoor unit is abnormal according to the detailed outdoor unit failure mode recall function.(Refer to 10-2.2)

Judgment of indoor/outdoor abnormality

Yes

(Blinks)

	Before blinking, does the left lamp of			Yes
	OPERATION INDICATOR lamp stay ON for 3
	seconds?
	Stays ON for 3 seconds (without beep):
	The outdoor unit is abnormal.
		No
	The indoor unit is abnormal.				The outdoor unit is abnormal.
	Check the blinking pattern, and confirm the abnormal point with the indoor unit				Check the blinking pattern, and confirm the abnormal point with the
	failure mode table (Refer to indoor unit service manual.)				outdoor unit failure mode table (Refer to 10-2.3).
	Make sure to check at least two consecutive blinking cycles.		W2		Make sure to check at least two consecutive blinking cycles. W3
Releasing the failure mode recall function
	Release the failure mode recall function by the following procedures.
	Turn OFF the power supply and turn it ON again.
	Press RESET button of the remote controller.
	Repair the defective parts.
Deleting the abnormal memorized condition

1After repairing the unit, recall the failure mode again according to "Setting up the failure mode recall function" mentioned above.

2Press OPERATE/STOP(ON/OFF) button of the remote controller (the set temperature is displayed) with the remote controller headed towards the indoor unit.

3Press EMERGENCY OPERATION switch so that the memorized abnormal condition is deleted.

4Release the failure mode recall function according to "Releasing the failure mode recall function" mentioned above.

Note1.Make sure to release the failure mode recall function once it's set up, otherwise the unit cannot operate properly. 2.If the abnormal condition is not deleted from the memory, the last abnormal condition is kept memorized.

W2. Blinking pattern when the indoor unit is abnormal:

Blinking at 0.5-	Blinking at 0.5-
2.5-second OFF second interval	2.5-second OFF second interval
ON
OFF
Beeps	Beeps	Beeps
Repeated cycle	Repeated cycle	Repeated cycle

W3.Blinking pattern when the outdoor unit is abnormal:

			Blinking at 0.5-				Blinking at 0.5-
	2.5-second OFF	3-second ON	second interval		2.5-second OFF	3-second ON	second interval
ON
OFF
		No beep		Beeps		No beep		Beeps
		Repeated cycle				Repeated cycle			Repeated cycle

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