Instructions | LG Air Conditioner PCB Short-Circuit Diagnosis.

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Step 1

1. Visual Inspection (The Blown Fuse): Spotting physical damage like shattered glass fuses and cracked components (NTC thermistor).
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Step 2

2. Multimeter Testing & Short Detection: Using a multimeter in diode/continuity mode to track shorts from the AC input to the switching regulator stage.
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Step 3

3. Component Removal & Verification: Desoldering damaged NTC thermistors and bridge rectifier/diodes (such as 1N4007 diodes), then re-testing the circuit traces.
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Step 4

4. Replacement & Reassembly: Installing new components, a fresh 3.15A fuse, and checking resistance values (moving from ohms/short to megaohms).
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Step 5

5. Safe Power-Up & Testing: Powering the board through a dim-bulb/series tester for safety, verifying standby state, and remote control testing.

LG Air Conditioner PCB Short-Circuit Diagnosis.