The SOS button light flashes orange instead of staying green.

If your "SOS fault" is actually related to low voltage from the vehicle's primary power source, you may need to replace the main battery instead. Standard Peugeot 2008 Spec Replacement Requirement 12V L2/L3 EFB or AGM (for Start/Stop) 10mm socket wrench, terminal sanding SOS Battery Specific Peugeot Backup Lithium Pack Trim tools, potential software reset

You’re comfortable with interior trim removal, basic soldering, and have a way to clear fault codes (or don’t mind the warning light lingering for a few days).