What can cause lights flicker?
Lights flicker can come from more than one starting & electrical branch. Operating conditions, warning behavior, scan data, and physical tests are needed to separate the supported cause from look-alikes.
Plausible causes
- Low-voltage supply, starting-control, or network fault
- Battery capacity, connection, or charging
- Key-off draw or network wake-up
Useful next checks
- Note how long the vehicle was parked, the click pattern, lamp behavior, recent jump or battery work, and any portable or aftermarket accessory. Inspect accessible terminals only with the vehicle off.
- Charge and battery capacity test
- Cranking and charging/DC-DC voltage-drop tests
Sources and method
This answer provides hypotheses and a verification plan, not a component verdict. Exact repair procedures require authoritative service information for the specific vehicle.
Battery Discharge Diagnostic Guidance · NHTSA / Subaru