The cargo and service compartments have a lighting system which supplies light to the aft equipment compartment and the external area around the baggage door.

The service compartment lighting system includes two aft equipment compartment lights, a baggage compartment external light, and an autoshutoff device. Two lights are installed in the aft equipment compartment. These lights supply light for general maintenance and inspection in the aft equipment compartment. The baggage compartment external light is in the left aft fuselage. The autoshutoff device, in the aft equipment compartment, supplies the 28 VDC power to the service compartment lights.

There are two lights installed in the aft equipment compartment. One is installed at FS760.00 on the right side. It is installed on the same bracket as one of the strobe light power supplies. The other light is installed at FS703.00 at aircraft centerline. It is installed on an overhead bracket near the autoshutoff device. The function of these lights is to supply light for general maintenance and inspection in the aft equipment compartment. The aft equipment compartment lights receive electrical power from the 28 VDC L BATT BUS through the autoshutoff device.

The autoshutoff device is installed in the aft equipment compartment at FS690.00 at aircraft centerline. It is installed overhead on the fire extinguisher containers bracket. The auto-shutoff device supplies the 28 VDC power to the service compartment lights. The autoshutoff device is controlled by the AFT COMP LIGHT switch or the BAG EXT LIGHT switch. These switches, when set, operate momentarily.

The baggage compartment external light is installed in the left aft fuselage at FS702.00. Because the light is installed where the skin has a curve, the light beam points down. Also, internally, the light is made to supply a light beam with an angle of 45 degrees forward. This installation is made to supply lighting of the ground area in front of the baggage loading area. The baggage compartment external light receives electrical power from the 28 VDC L BATT BUS through the autoshutoff device.

The aft equipment compartment lights are controlled by the AFT COMP LIGHT switch through the autoshutoff device. The AFT COMP LIGHT switch is in the aft equipment compartment, aft of the door, on a bracket attached to the left leg of the aft equipment compartment floor at FS756.25.

The baggage compartment external light is controlled by the BAG EXT LIGHT switch through the autoshutoff device. The BAG EXT LIGHT switch is installed in the aft fuselage, forward of the door, on a bracket attached to the frame at FS641.75. When one or the other switch is pushed one time, the autoshutoff device supplies electrical power to the lights for a period of 20 minutes. After 15 minutes in usual operation, the light automatically flashes at 1.5 second intervals for a period of 10 seconds. The light flashes on during 1.25 seconds and goes off for the remaining 0.25 seconds for a total of 1.5 seconds. Then it reverts to usual operation for approximately 5 minutes. After 20 minutes, the auto-shutoff device automatically changes to the standby operation (lights off). If a switch is pushed before the 20 minutes is completed, a new period of time is started. The autoshutoff device can be changed from the usual operation (lights on) to the standby operation (lights off) when one switch is pushed two times quickly.