Message Name:

GROUP OF INTEGRAL LIGHTS WILL NOT COME ON

A defective COCKPIT LIGHTS (INTEGRAL) Control Panel would cause:

• a group or groups of Integral/Miscellaneous Lights do not come on (Light bulbs are serviceable)
• DIM/BRT Switch cannot control the intensity of a group of lights
• DIM/BRT Push Button Annunciator (PBA) Toggle Switch does not change the intensity of the Annunciator Lights
• MASTER Integral Light Switch has a malfunction

• Light Switch
• Cockpit Lights (Flood/Display) Control Panel (AP27)
• Cockpit Lights (Integral) Control Panel (AP26)
• Associated Wiring

Advisory Wire/Service Bulletin: None

Forum Articles/Infoservice/Newsletter: None

1. Check if a DIM/BRT rotary switch or a PBA toggle switch change the intensity of a group of integral lights.

   1. If a DIM/BRT rotary switch or a PBA toggle switch does not change the intensity of a group of integral lights, go to step 4.
   2. If a DIM/BRT rotary switch or a PBA toggle switch change the intensity of a group of integral lights, continue with next step.

2. Measure the voltage at the connectors as follows:

   Light	From	To	Expected Result	Result
   For the L integral lights	AP26P1-11	AP26P1-12	28 VDC
   For the CTR integral lights	AP26P1-9	AP26P1-10	28 VDC
   For the CTR integral lights	AP26P1-13	AP26P1-10	28 VDC
   For the CTR integral lights	AP26P1-14	AP26P1-10	28 VDC
   For the CTR integral lights	AP26P1-15	AP26P1-10	28 VDC
   For the R integral lights	AP26P2-11	AP26P2-12	28 VDC
   For the OVHD integral lights	AP26P2-9	AP26P2-10	28 VDC
   For the CB integral lights	AP26P2-13	AP26P2-14	28 VDC
   For the AREA lights	AP26P1-22	AP26P1-17	28 VDC
   For the FLOOR and EYE REF lights	AP26P1-22	Ground	28 VDC

   1. If there is voltage, go to step 5.
   2. If there is no voltage, continue with next step.

3. Perform a wiring check as follows:

   Switch	From	To	Result
   For the MASTER switch	AP26P1-6	Ground
   For the MASTER switch	AP26P1-16	Ground
   For the PBA switch	AP26P1-33	Ground
   For the PBA switch	AP26P1-34	Ground
   For the PBA switch	AP26P1-36	Ground
   For the PBA switch	AP26P1-37	Ground
   For the PBA switch	AP26P2-7	Ground
   For the PBA switch	AP26P2-8	Ground

   1. If wiring checks are not good, repair defective wiring as required and do close out.
   2. If wiring checks are good, continue with next step.

4. Replace COCKPIT LIGHTS (INTEGRAL) Control Panel.

   1. If system checks are good, do close out.
   2. If fault remains, continue with next step.

5. Replace the COCKPIT LIGHTS (FLOOD/DISPLAY) Control Panel.
6. Do close out.