What was found
EMERGENCY LIGHTS OPS CHK, EMERGENCY LIGHTS INOPERATIVE AT SEAT 15ABC, 20ABC & 21ABC.ALL EMERGENCY AISLE LIGHTS TURN OFF WITHIN A FEW SECS TURNING THEM ON. CHARGING BATTERY FOR 90 MINS BEFORE CONTINUEING TROUBLESHOOTING IAW AMM 33-50-801 AFTER LETTING BATTERY CHARGE, ALL ISLE EMERGENCY LIGHTS CAME ON EXCEPT FOR THE EMERGENCY EXIT ROW LIGHTS WHICH STAYED OFF, WITHIN A FEW SECS ALL LIGHTS FWD OF ROW 15 SHUT DOWN. FURTHER TROUBLESHOOTING REQUIRED IAW AMM 33-50-801. PERFORMED OPS CHECK OF LIGHTS & FOUND ALL LIGHTS WOULD WORK EXCEPT OVERWING ESCAPE HATCH AISLE SEAT LIGHTS. R & R POWER SUPPLY M1694 IAW AMM 33-51-06-960-806. WAITED THE 90 MINS FOR BATTERIES TO RECHARGE. DURING THE OPS CHECK ALL LIGHTS CAME ON BUT AFTER A FEW MINUTES SEATS 14 THROUGH 7 AISLE LIGHTS TURNED OFF. SEAT 20 ONE RED LIGHT WON'T TURN ON EITHER. ORIGNAL INOP OVERWING ESCAPE HATCH AISLE LIGHTS NOW WORK. SUSPECT ANOTHER POWER SUPPLY GOING BAD. PANEL THAT COVERS BATTERY WILL NEED TO BE REPLACED. ONE LATCH IS BROKEN & HARD TO PUT ON. FOR SEATS 14-7 OBSERVED EMERGENCY LIGHTS GOING OUT APPROX 15 SECS AFTER BEING TURNED ON. FOUND POWER SUPPLY INSTALLED PWR SUPPLY & BATTERY ASSY AT SEAT 8F IAW AMM 33-51-06-960-806, ALL EMERGENCY LIGHT OPS NORMAL. TEST OF PWR SUPPLY IS NORMAL. SYSTEM CONSIDERED SERVICABLE.