What was found
FT # 466, RSW-BOS. HAD BATTERIES TO EMER EXIT LIGHTS CHANGED, THINGS WORKED. HAD ON PWR TRANSFER FROM EXTERNAL POWER TO APU, ALL EXIT LIGHTS CAME ON AND REMAINED ON W/ SWITCH IN ARM POSITION; R & R EMER EXIT LT SWITCH (4WL) IAW ESPM 20-45-21. ALL OPS NORMAL AT THIS TIME. A/C OK FOR SVC.