A practical guide from a Chicago sign shop on why your business sign stopped working, what's likely wrong, and how to get it fixed fast.
It's 8pm on a Tuesday in Chicago. You're closing up. You step outside, look back at the building, and realize your sign is dark. Or half-lit. Or flickering like it's auditioning for a horror movie. And now you're standing on the sidewalk wondering: is this a today problem, a tomorrow problem, or a "the whole sign is shot" problem?
After 35 years of fixing signs across Chicagoland, we can tell you: it's usually one of about six things. None of them mean you need a brand-new sign. Here's how to figure out what's going on.
The one-question test
Is your sign completely dark, or partly out / flickering?
That single distinction tells us most of what we need to know.
- Completely dark = usually a power issue, transformer, or main wiring problem
- Partly out / flickering = usually an LED module, individual neon section, or photocell issue
- One letter only = almost always isolated LED, ballast, or wiring at that letter
Once you know which bucket you're in, the rest of the diagnosis gets faster.
If your sign is completely dark
Start by checking the breaker. Sounds simple. We've driven across the city for "the sign is dead" calls that turned out to be a tripped breaker after a storm. Check the panel that feeds your sign first. If it's tripped, reset it. If it trips again immediately, stop — there's a short somewhere and you need a professional.
If the breaker is fine, the most common causes are:
- Failed transformer. Most lit signs run on a transformer (or several). When one dies, an entire section goes dark. Transformers fail from age, water intrusion, or electrical surges — Chicago summer storms are brutal on them.
- Photocell failure. If your sign is supposed to turn on automatically at dusk, the photocell sensor might be stuck or broken. The sign reads the wrong light level and never wakes up.
- Main wiring fault. Water, rodents (yes, really), or a poorly-aged junction box can break the main power feed. This is the worst-case scenario for a "totally dark" sign and almost always needs a professional repair.
If your sign is flickering or partly out
Flickering signs are usually warning you about something. Don't ignore it — the cost to repair a flickering sign goes way up if you wait until it dies completely and takes the transformer with it.
Common causes:
- Failed LED module. Modern channel letters and cabinet signs use rows of LED modules behind the face. When one module dies or a connection corrodes, you get partial darkness or flicker. Most LED sign repair work is a quick swap of the failed module or driver — no need to rebuild the whole sign.
- Aging ballast (fluorescent signs). If your sign is older and uses fluorescent tubes, ballasts wear out. Flickering, then dim, then dark.
- Neon section issue. Neon signs can have individual sections fail. A transformer might still be running, but a section won't light if the gas tube is cracked or the electrode is shot.
- Loose wire connection. Vibration, wind, and 35-year-old wire nuts catch up to every sign eventually. Sometimes it really is just a loose connection — but you can't fix it from the sidewalk.
If only one letter is out (channel letter signs)
The letter has its own power and its own LEDs. When one letter goes dark, it's almost always:
- A failed LED module inside that letter
- A failed driver (the small power unit that runs that letter's LEDs)
- A wiring break at the letter's junction point
This is one of the easiest and cheapest channel letter sign repair jobs we do — usually a same-day fix once we're on site.
What it costs to repair (Chicago ranges)
We get this question a lot, so here's straight talk on typical ranges:
- Single letter fix: $300–$700
- Transformer or driver replacement: $500–$1,200
- Photocell repair: $300–$600
- Multiple LED modules / partial rebuild: $750–$2,500
- Major wiring repair: $900–$3,500+
These are real-world Chicago ranges for commercial sign repair. If a quote is way under, ask what's actually being replaced. If it's way over, ask why.
When to call a pro vs. wait it out
Call same-day if:
- The sign is sparking, smoking, or you smell anything burning. Cut power at the breaker and call.
- The sign is leaning, sagging, or you can see exposed wires from the street.
- It's storm season and water might be inside the cabinet.
Can probably wait 24–48 hours if:
- The sign is partially dark but stable (not getting worse)
- A single letter is out
- The sign is flickering at the same intensity, not actively dying
But we'll be honest: most Chicago business owners don't want a half-lit sign telling customers they're either closed or don't care. The longer it sits, the worse it looks.
A word about our shop
Rick Signs and Repairs has been a Chicago father-and-son sign shop since 1989. We work on neon, LED, channel letters, monument signs, awnings, storefronts — the full range of business signs you see across the Chicagoland area. Most of our work is repair, because most of our calls start the way yours might: somebody noticed something was wrong and wanted it fixed quickly.
If you're staring at a dark or flickering sign and need a real diagnosis, we offer emergency sign repair across Chicago and the suburbs, and we work with neon, LED, and channel letter signs of every type.
Bottom line
If your business sign stopped working, it's almost always one of six things — and almost none of them require a new sign. Check the breaker, look at whether it's fully dark or partly out, and call a pro the same day if anything looks unsafe.
A working sign is one of the cheapest forms of advertising your business has. Don't let it stay broken.
Related reading
- Neon Sign Repair in Chicago: Cost, Process, and When It's Worth It (coming soon)
- Commercial Sign Repair in Chicago: How to Find a Vendor You Can Trust (coming soon)
- Channel Letter Sign Repair: How Channel Letters Work and What Goes Wrong (coming soon)
Got a sign that needs a look? Call Rick Signs at (773) 815-0006 or request a repair quote.