A flashing light is a fault signal, not the root cause itself. Most cases map to protection triggers, communication faults, or sensor/control instability.
Note your answers to these three questions. They take 30 seconds and will point you to the right fault path.
Most common · Needs diagnosis
When unsafe load or temperature conditions are detected, the unit can stop operation and flash repeatedly.
Watch out: Treating the blink as a board-only issue can miss the physical trigger and lead to repeat faults.
Recurring error cycle · Needs diagnosis
Signal loss or unstable control handoff between indoor and outdoor sections can produce recurring flash cycles.
Watch out: Replacing parts without validating signal path behavior can leave the same fault active.
Less common · Needs diagnosis
Unstable sensing or control logic can generate fault signaling that mimics other failure paths.
Watch out: Swapping one board first can bypass upstream triggers and increase unnecessary scope.
Brief mains instability can trigger a temporary fault latch. The flash pattern may look serious, but the issue may not persist once power quality stabilizes.
If this is the case we will tell you directly before recommending deeper repair scope.
| Finding | Next Step |
|---|---|
| Repeat protection-trigger pattern | Isolate overload trigger and retest |
| Consistent communication-drop behavior | Verify communication path before parts replacement |
| Irregular blink with unstable control behavior | Run focused sensing and control diagnostics |
| One-off event tied to power disturbance | Monitor stability and verify return to normal |
| Pattern unclear on first pass | Retest under normal operating conditions |
No disassembly needed. Just observe:
The more specific you are, the faster we point you to one next step.
These are not routine flashing faults. These are safety issues.