As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT ATT REPORTS EXIT SIGNS/LIGHTS ABOVE L2,R2, & AFT GALLEY CEILING WERE INTERMITTENTLY FLASHING DURING BOARDING, FLIGHT AND AFTER ARRIVAL. GROUNDED - YES. ACCOMPLISHED B737-900 AMM 33-51-00-720-801 EMERGENCY LIGHTS OPERATIONAL CHECK PERFORMED FOUND OK. AIRCRAFT POWER RESET CARRIED OUT EMERGENCY LIGHTYS FUNCTION FOUND NORMAL. INSPECTED LIGHTS @ AFT GALLEY FOR EMERGENCY LIGHTS FOUND NO DEFECTS.