Lighting Troubleshooting

The Lighting Troubleshooting SOP defines a structured, methodical approach to diagnosing and resolving lighting system issues during prep, load-in, rehearsal, and show operation. Consistent troubleshooting prevents panic-driven changes, reduces downtime, and ensures problems are resolved safely and efficiently.

This SOP applies to all lighting-related issues involving fixtures, data, power, consoles, and networking.

Purpose

  • Provide a repeatable process for diagnosing lighting problems.

  • Minimize show disruption caused by technical failures.

  • Prevent unsafe or unnecessary changes under pressure.

  • Ensure issues are documented for post-show repair and improvement.

  • Support clear communication between technicians, leads, and PMs.

Core Troubleshooting Principles

Always follow these principles:

  • Stay calm – Panic causes mistakes.

  • Change one thing at a time – Never shotgun fixes.

  • Verify assumptions – Do not assume something is correct.

  • Start simple – Power and data first.

  • Document issues – Even if resolved quickly.

  • Escalate when needed – Do not hide problems.

Troubleshooting Workflow

Follow this order unless safety dictates otherwise:

  1. Safety Check

  2. Power

  3. Data

  4. Addressing / Patch

  5. Console / Network

  6. Fixture Hardware

  7. Environmental Factors

1. Safety Check

Before touching anything:

  • Ensure no exposed conductors.

  • Verify fixtures are secure.

  • Do not work on live power unless approved.

  • Clear personnel from unsafe areas.

If the issue presents a safety risk, stop immediately and escalate.

2. Power Issues

Common Symptoms

  • Fixture not powering on

  • Random resets

  • Flickering output

  • Breakers tripping

Checklist

  • Confirm circuit is energized.

  • Verify correct voltage.

  • Check connector seating.

  • Inspect power cable for damage.

  • Verify distro breaker status.

  • Confirm load is not exceeding limits.

If power is unstable, do not continue troubleshooting data until resolved.

3. Data Issues

Common Symptoms

  • Fixture powers on but does not respond

  • Intermittent response

  • Erratic behavior

Checklist

  • Confirm data cable connection.

  • Swap in a known-good cable.

  • Verify correct protocol (DMX / Art-Net / sACN).

  • Confirm node output is active.

  • Check DMX termination if required.

  • Bypass splitters to isolate the problem.

Always test with a single known-good fixture when isolating data issues.

4. Addressing & Patch

Common Symptoms

  • Wrong fixture responding

  • Multiple fixtures moving together

  • No response on expected controls

Checklist

  • Verify fixture mode.

  • Confirm starting address.

  • Check universe assignment.

  • Compare console patch to physical labels.

  • Ensure no address overlap.

Addressing mismatches are the most common lighting issue—verify carefully.

5. Console & Network

Common Symptoms

  • Universes not outputting

  • Network nodes offline

  • Delayed or dropped response

Checklist

  • Verify output is enabled.

  • Confirm correct IP addressing.

  • Check subnet compatibility.

  • Power-cycle nodes or switches if needed.

  • Check for duplicate IP addresses.

  • Confirm console software stability.

Do not update console software during troubleshooting unless approved.

6. Fixture Hardware

Common Symptoms

  • Mechanical noise

  • Loss of pan/tilt accuracy

  • Color wheel errors

  • Gobo wheel stuck

  • Overheating warnings

Checklist

  • Power-cycle the fixture.

  • Inspect fans and vents.

  • Check for physical obstructions.

  • Reset fixture parameters if applicable.

  • Swap fixture with a known-good unit if necessary.

Faulty fixtures should be removed from the rig if possible.

7. Environmental Factors

Consider:

  • Excessive heat

  • Moisture or condensation

  • Dust buildup

  • Unstable power sources

  • RF interference (for wireless systems)

Environmental issues often cause intermittent failures.

Escalation Guidelines

Escalate immediately if:

  • A safety issue is identified

  • Multiple fixtures fail simultaneously

  • Power distribution behaves abnormally

  • The issue threatens show continuity

  • You are unsure how to proceed safely

Escalation path: 1. Crew Lead 2. Lead Lighting Tech / Programmer 3. Project Manager or TD

Documentation Requirements

All significant issues must be documented:

  • Fixture or system affected

  • Symptoms observed

  • Steps taken

  • Resolution (if found)

  • Items needing repair or replacement

Documentation should be entered into: - Job notes - Repair intake system - Post-show report

Common Mistakes to Avoid

  • Making multiple changes at once

  • Ignoring power warnings

  • Skipping address verification

  • Hot-swapping non-rated connectors

  • Blaming the console without evidence

  • Failing to document resolved issues

Post-Show Follow-Up

After the event:

  • Tag affected equipment.

  • Route to repair or maintenance.

  • Update SOPs if a recurring issue is identified.

  • Review troubleshooting notes with the team.

Lessons learned should improve future shows.