Sanyo SAP-KRV94EHDX service manual Troubleshooting, Method of Self-Diagnostics, Procedure

10. TROUBLESHOOTING

10-1. Precautions before Performing Inspection or Repair

After checking the self-diagnostics monitor, turn the power OFF before starting inspection or repair.

High-capacity electrolytic capacitors are used inside the outdoor unit controller (inverter).They retain an electrical charge (charging voltage DC 310 V) even after the power is turned OFF, and some time is required for the charge to dissipate. Be careful not to touch any electrified parts before the controller LED (red) turns OFF.

If the outdoor controller is normal, approximately 30 seconds will be required for the charge to dissipate. However, allow at least 5 minutes for the charge to dissipate if there is thought to be any trouble with the outdoor controller.

After repairs are carried out, be sure to press and hold the TEST RUN button until the buzzer sounds 2 times to erase the diagnosis results.

10-2. Method of Self-Diagnostics

If the indoor unit operation lamp is blinking every 0.5 seconds, follow the procedure below to perform detailed trouble diagnostics.

NOTE

1.If the operation lamp blinks every 0.5 seconds immediately when the power is turned ON, there is an external ROM (OTP data) failure on the indoor circuit board or ROM socket insertion problem, or the ROM has not been installed. Make sure the ROM is in existence.

2.The failure mode is stored in memory even when the power is not ON. Follow the procedure below to perform diagnostics.

Main unit controller

TEST RUN button

ON/OFF operation button

PROCEDURE

1.Turn the power supply switch ON. However, the A/C itself should remain stopped.

2.Press and hold the TEST RUN button on the main unit controller until the buzzer sounds 1 time. At this time, releasing the TEST RUN button starts self-diagnostics.

3.If there is a sensor failure or a protective function has activated, self-diagnostics lamps 1, 2, and 3 will illuminate in the following pattern: 5 seconds blinking (illuminated) + 2 seconds OFF. (Buzzer sounds once while lamps are OFF.)

NOTE If there is no trouble, then self-diagnostics lamps 1, 2, and 3 do not illuminate, and the buzzer does not sound.

4.Diagnostics is completed when the buzzer sounds 3 times.

<IMPORTANT> After repairs are carried out, be sure to press and hold the TEST RUN button until the buzzer sounds 2 times. When the TEST RUN button is released, the buzzer sounds 1 long beep, and the diagnosis results are erased.

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