Here are the most common issues our customers report with commercial LED lighting and the most likely causes and solutions for each. If you've worked through these and still have a problem, contact us to discuss a warranty claim.

For a general pre-claim troubleshooting checklist, see EDU-004: General Troubleshooting Before Filing a Warranty Claim.

Issue: Fixture Won't Turn On

Likely causes and what to check:

1. No power to the fixture: Verify the circuit is live with a meter at the fixture's input terminals. Check for a tripped breaker.
2. Wrong input voltage: Confirm the fixture's rated input voltage matches what's on the circuit. Most commercial LED fixtures are rated 120 to 277V universal voltage, but verify on the spec sheet.
3. Loose wiring connection: Inspect all wire connections at the fixture. A loose wire nut or terminal is one of the most common causes of no-light on a new install.
4. Driver in protection mode: Some drivers shut down when they detect a wiring fault or overtemperature. Cut power for 30 seconds, restore, and see if the fixture comes back on.
5. Emergency backup battery issue: If the fixture has an emergency battery pack, confirm it's wired correctly or bypassed per the installation manual. A wiring error in the emergency circuit can prevent normal operation.

Issue: Flickering

Likely causes:

1. Dimmer incompatibility: This is the most frequent cause. Confirm the dimmer type matches the fixture's protocol (TRIAC, ELV, 0-10V). Check the manufacturer's dimmer compatibility list. See EDU-001: Line Voltage vs. Low Voltage Dimming.
2. Minimum load issue: Some dimmers need a minimum load to function properly. Too few LED fixtures on a circuit designed for heavier incandescent loads can cause flickering.
3. 0-10V wiring issue: For 0-10V dimmable fixtures, confirm polarity is correct and there are no intermittent connection issues on the control leads.
4. Loose wiring: Even a partially loose connection can cause intermittent flickering under load.
5. Voltage fluctuations on the circuit: If multiple circuits flicker simultaneously, the issue may be upstream. Check for a power quality problem.

Quick test: Wire the fixture directly to line voltage without going through the dimmer. If flickering stops, the dimmer is the issue.

Issue: Wrong Color Temperature (Color Looks Too Warm or Too Cool)

What to check:

1. Confirm you received the correct CCT: Check the label on the fixture itself and compare it to your order. Part number mix-ups happen.
2. Color-selectable fixture: Many fixtures come with selectable CCT via DIP switches. If the switches are in the wrong position, the fixture will output a different color than intended. Review the installation manual.
3. Tunable white fixture not getting a control signal: If the fixture is tunable white (adjustable CCT via 0-10V or DALI), it may default to one end of the range if no signal is present.
4. Cold ambient temperature: LEDs shift slightly cooler in very low temperatures and return to rated CCT once they warm up. If this is a new install in an unheated space, give it time to warm up and check again.

Issue: Fixture Is Dim or Noticeably Less Bright Than Expected

What to check:

1. 0-10V lead issue: The most common cause on dimmable fixtures. If the 0-10V leads are left floating (not connected) or connected to a 0V source, many drivers will default to a reduced output level. Confirm the control leads are properly terminated or shorted together (which typically signals full output on most 0-10V drivers).
2. Dimmer set to reduced output: Check whether a dimmer or control system is holding the fixtures at a reduced level.
3. Incorrect fixture: Verify the fixture's rated lumens match what you expected. Some fixture model lines have similar part numbers at different wattages.
4. Driver issue: Compare against a known-good unit from the same batch. If one fixture is consistently dimmer than others on the same circuit with no control signal, the driver may be faulty.

Issue: Buzzing, Humming, or Audible Noise

What to check:

1. Dimmer compatibility: Audible hum at reduced dim levels is a classic sign of a dimmer/driver mismatch. Try a different compatible dimmer.
2. Noise from the dimmer, not the fixture: Hold your ear close to the dimmer itself. Many of the complaints attributed to fixtures are actually coming from the wall-box dimmer or occupancy sensor.
3. Loose fixture components: Confirm all mounting hardware, lenses, and housing screws are tight. Vibrating panels create noise.
4. Driver noise at full power: Some LED drivers produce a faint, high-frequency whine. This is generally a driver-quality issue and won't go away. If it's unacceptable for the application, contact us about a substitute.

Issue: Fixture Starts and Then Shuts Off

What to check:

1. Overtemperature protection: LED drivers have built-in thermal protection that shuts the unit down if it overheats. This is usually caused by inadequate thermal path (fixture mounted against insulation, inadequate ventilation, or a driver not seated properly in its housing).
2. Voltage sag under load: On large installations, check that the supply voltage doesn't drop below the fixture's minimum input voltage when the full load is energized.
3. Short circuit or wiring fault downstream: Check for a pinched wire or loose connection that's causing an intermittent fault.

Issue: Occupancy or Daylight Sensor Not Functioning

What to check:

1. Wiring: Sensor integration wiring varies between products. Review the wiring diagram in the installation manual carefully.
2. Sensitivity setting: Adjust the sensitivity dial or DIP switch if the sensor isn't detecting occupancy in the coverage zone.
3. Coverage area: Confirm the sensor's coverage pattern includes the area you're trying to control. Check for obstructions.
4. Time delay setting: If the fixture shuts off too quickly or stays on too long, check the time-delay adjustment on the sensor.
5. Power to sensor: Confirm the sensor is receiving power. Some sensors require a dedicated neutral.

When to Contact Us

If none of the steps above resolve your issue, it's likely a product defect and a warranty claim may be warranted. Contact us with:

• Your order number
• Product name and part number
• A description of what you've already tried
• Photos or video of the issue (very helpful for damage or visible defects)

Contact us:

• Email: support@relightdepot.com
• Phone: 888-548-6387, Mon to Fri, 8 AM to 8 PM ET
• Ticket: https://help.relightdepot.com/portal/en/newticket