15

Symptom: MGTC-20, DXTC-20, DXTH-20 – ERROR CODE EF

Solution: MULTIPLE SOLUTIONS

Cause: OUTDOOR FAN MOTOR FAULT (DC FAN MOTOR)

Remarks:

DESCRIPTION:

DC FAN MOTOR DEFECT OR FAILURE FROM FAN MOTOR CONTROL BOARD.

REPAIR:

1) SWITCH OFF THE POWER, THEN SWITCH IT BACK ON. IF THE FAULT REMAINS, CHECK CONNECTION OF CN12-1, CN12-2:

SOLUTION 1) PLEASE RECONNECT AGAIN IF NEEDED

2) CHECK THE SOLDERING OF THE CONNECTOR CN12-1, CN12-2 ON THE PCB, THERE SHOULD NOT BE PSEUDO SOLDERING:

SOLUTION 2) IF THERE IS PSEUDO SOLDERING, PLEASE SOLDER AGAIN

3) REPLACE THE DC MOTOR AND CHECK ITS ACTION:

SOLUTION 3) IF THE PROBLEM DOES NOT CHANGE, PLEASE REPLACE OUTDOOR PCB

4) SWITCH OFF AC UNIT AND TEST U/V; U/W; V/W ON CN12-2, THERE SHOULD NOT BE A SHORT CIRCUIT HAPPENING:

SOLUTION 4) IF SHORT CIRCUIT DOES HAPPEN, PLEASE REPLACE OUTDOOR PCB

5) TEST BETWEEN PINS OF IPM (IC13), NO BREAKDOWN OR SHORT CIRCUIT SHOULD HAPPEN:

SOLUTION 5) IF SHORT CIRCUIT DOES HAPPEN, PLEASE REPLACE OUTDOOR PCB

6) TEST VOLTAGE OF PIN 7 ON IC14, IT SHOULD BE +5V:

SOLUTION 6) IF NOT, PLEASE REPLACE OUTDOOR PCB

7) TEST VOLTAGE OF PIN 22 (SIGNAL F0) ON IC13, IT SHOULD BE +5V:

SOLUTION 7) IF NOT, PLEASE REPLACE OUTDOOR PCB

8) TURN POWER OFF, CHECK FAN MOTOR BY HAND:

SOLUTION 8) CAN IT MOVE OR NOT? IF THERE IS ANY BLOCKAGE, PLEASE REMOVE IT

9) CHECK THE WIRING AND/OR CONNECTION FROM MOTOR TO PCB:

SOLUTION 9) CHECK IF THERE IS ANY LOOSE/BROKEN WIRE OR CONNECTION FROM MOTOR TO PCB.