Start at the wall and work back to the lamp
Before assuming failure, establish what the unit did on day one. Most store logo projection light complaints describe a gradual decline that nobody dated, which makes it impossible to tell a failing LED from a dirty lens. Take a photo, note the hour and the house lighting, and compare against the install record.
The image is soft or out of focus
A soft image that appeared gradually is usually contamination, not optics failure. Dust on the internal lens or a film on the gobo scatters light and lowers contrast, which reads as blur. Clean in the order the light travels and re-check before ordering anything.
- Refocus at the working hour on the actual surface
- Check the corners — soft corners mean an angled mount
- Confirm the surface is flat
- Inspect the lens and gobo for contamination
Dim: ambient light, output and dirty optics
Before blaming the LED, clean the optics and check the duty cycle. A store logo projection light that runs hot in an enclosed void will dim progressively as the driver protects itself, and the symptom looks exactly like lamp wear. Logging the housing temperature over a full evening will separate the two.
- Clean the outer window and lens
- Measure ambient light at the working hour
- Reduce the image width and re-check contrast
- Run a full duty cycle and log the housing temperature
Colour and artwork faults
Most colour complaints turn out to be artwork, not hardware. A gobo engraved from a low-resolution file, or one where a gradient was converted to a coarse halftone, produces banding and muddy edges that look like a projector fault. Check the original file before ordering replacement optics.
It cuts out, hums or trips
Note the timing. Cut-out after 60–90 minutes is thermal; a trip at switch-on is inrush or a wiring fault; a hum that appears only at full output is the driver. All three are fixable without replacing the store logo projection light, but all three get misdiagnosed as a dead unit when nobody records when the fault occurs.
When to stop and call the manufacturer
Stop diagnosing and call when you have eliminated the three cheap causes: contamination, ambient light and supply. Before you do, gather the serial number, the install date, and a photograph of the image on the wall at the working hour. A supplier can usually resolve it from those without a site visit.
- Model and serial number
- Install date and daily run hours
- Throw distance and image width
- A photograph of the fault at the working hour