Most solar inverter faults are first spotted as a coloured light, long before anything stops working. Here is what the common indicators mean — and which ones can wait, and which ones cannot.
The common indicator colours
- Solid green — normal operation, converting power
- Blinking green — starting up, or normal in some models during data communication
- Solid yellow/orange — warning: derated, waiting on grid, or a non-critical alert
- Solid red — fault: the inverter has stopped or restricted output
- Flashing red — active fault needing prompt attention
- No light at all — no DC input, no AC supply, or an internal power failure
What each type of indicator usually points to
Green then red at startup usually means a grid or insulation check failed. Red appearing only at midday suggests high grid voltage or overheating. A completely dark display with good sunshine points to a blown fuse, failed auxiliary supply or a tripped isolator rather than a panel problem.
What to do before calling
- Note the exact colour and whether it flashes (count the pattern)
- Take a photo of the display showing any error code
- Check the AC breaker and DC isolator are ON
- Check the app — when did generation stop?
- Do not open the inverter under any circumstances
Frequently asked questions
My inverter light is red but power is still flowing — is that okay?
Some inverters run on reduced output while showing a warning. A persistent red light means an active fault — it should be diagnosed even if generation continues, because it usually precedes a shutdown.
Need a solar inverter repaired?
Share your inverter brand, model and error code — our technicians will guide you and share an estimate before any repair starts.