Start at the wall and work back to the lamp
Diagnose in the order the light travels: surface, then focus, then gobo, then lamp, then power. That sequence finds most LED gobo projector faults in under an hour, and it prevents the common mistake of replacing a perfectly good unit because the wall turned out to be the problem. Start by asking what changed — a fault that appeared overnight has a different cause from one that crept in over a season.
- What the surface looks like and how it is lit
- Whether the image is uniformly soft or soft at one edge
- When the fault started — overnight or gradually
- Whether anything on site changed at the same time
The image is soft or out of focus
Refocus at the working hour, on the actual surface, and check the corners as well as the centre. If the corners never sharpen, the LED gobo projector is off-axis rather than out of focus — move the bracket rather than the lens. If focus drifts again after a week, look for vibration or a focus mechanism without a lock.
- 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
Check the easy things in order: lens cleanliness, ambient light at the working hour, image size. Halving the image area doubles the brightness at the wall, which is free. Only after those should you consider a higher output model — and if you do, note that going from 15 W to 300 W is a visible but not dramatic change.
- 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
If the whole image has shifted, suspect the filter; if only part has, suspect the gobo. Dichroic coatings are stable for years, but dyed glass browns under heat, and an LED gobo projector running at the top of its range will age a cheap filter in a single season. Photograph the image against a white reference and compare it with the install photo.
It cuts out, hums or trips
Check the supply before the fixture. an LED gobo projector on a long cable run, a shared circuit, or a supply with its protection sized for something else will misbehave in ways that look like product failure. Measure at the unit under load, not at the distribution board.
- Note when the fault occurs — at switch-on or after warm-up
- Measure the supply at the unit under load
- Check the housing temperature and ventilation
- Confirm the protective device is correctly sized
When to stop and call the manufacturer
Call the manufacturer when the fault survives the sequence: optics cleaned, focus reset at the working hour, ambient light measured, and supply checked under load. Have the model, the install date, the throw distance and a photo of the image ready — that is enough for a supplier to tell you whether it is a warranty matter or a site issue.
