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LED Panels & Ceiling Lights · Partial outage

Locating and Replacing a Failed LED on a Light Board

A step-by-step troubleshooting guide that checks power, wiring, settings, and the affected component before parts are replaced.

DifficultyAdvancedTime30–90 minSteps6
FAULT OVERVIEW

Understand the symptom before replacing parts

A step-by-step troubleshooting guide that checks power, wiring, settings, and the affected component before parts are replaced.

Locating and Replacing a Failed LED on a Light Board — complete English tutorial infographic
English tutorial overview Complete English infographic with the six diagnostic or repair steps shown below.
TOOLS

Prepare before testing

  • Digital multimeter
  • Suitable inspection tool
  • Tweezers
  • Suitable inspection tool
!Safety note

Use the product label and wiring diagram as the final authority.

COMMON CAUSES

Check these areas first

  • Power or voltage mismatch
  • Loose, reversed, or damaged connection
  • Controller, driver, or component failure
  • Incorrect setting or incompatible device
STEP BY STEP

Diagnostic procedure

Follow the sequence and change only one condition at a time.

01

Disconnect mains power and verify it is off

Do not remove the fixture or touch internal wiring until the circuit is isolated.

Locating and Replacing a Failed LED on a Light Board — step 1: Disconnect mains power and verify it is off
Step 01: Disconnect mains power and verify it is off — Cropped directly from this tutorial’s English main infographic.
What to observeRecord the reading or behavior before changing the next variable.
02

Inspect terminals, switch connections, and visible damage

Look for loose wires, discoloration, swelling, odor, or heat marks.

Locating and Replacing a Failed LED on a Light Board — step 2: Inspect terminals, switch connections, and visible damage
Step 02: Inspect terminals, switch connections, and visible damage — Cropped directly from this tutorial’s English main infographic.
What to observeRecord the reading or behavior before changing the next variable.
03

Compare cold-start and warm behavior

Note whether the fixture flickers immediately, after heating, or only at low dimmer settings.

Locating and Replacing a Failed LED on a Light Board — step 3: Compare cold-start and warm behavior
Step 03: Compare cold-start and warm behavior — Cropped directly from this tutorial’s English main infographic.
What to observeRecord the reading or behavior before changing the next variable.
04

Use a compatible known-good driver for comparison

Qualified personnel can use substitution testing instead of probing exposed mains circuitry.

Locating and Replacing a Failed LED on a Light Board — step 4: Use a compatible known-good driver for comparison
Step 04: Use a compatible known-good driver for comparison — Cropped directly from this tutorial’s English main infographic.
What to observeRecord the reading or behavior before changing the next variable.
05

Inspect the LED board and individual LEDs

Look for darkened LEDs, cracked solder joints, or an open series string.

Locating and Replacing a Failed LED on a Light Board — step 5: Inspect the LED board and individual LEDs
Step 05: Inspect the LED board and individual LEDs — Cropped directly from this tutorial’s English main infographic.
What to observeRecord the reading or behavior before changing the next variable.
06

Replace the failed module and run a heat test

Confirm stable brightness, no flicker, and acceptable temperature after repair.

Locating and Replacing a Failed LED on a Light Board — step 6: Replace the failed module and run a heat test
Step 06: Replace the failed module and run a heat test — Cropped directly from this tutorial’s English main infographic.
What to observeRecord the reading or behavior before changing the next variable.
Expected result

The fault is isolated to a power source, connection, setting, controller, driver, or light section.

If the fault remains

Stop if there is overheating, odor, damaged insulation, repeated fuse failure, or exposed mains voltage.