EPSU - External Load Fault
TASK 33-51-00-810-808-A
EPSU - External Load Fault
1. Possible Causes
A. Referenced Information
3. Fault Confirmation
Subtask 33-51-00-810-074-A ** ON A/C NOT FOR ALL
Subtask 33-51-00-860-071-A ** ON A/C NOT FOR ALL
[Rev.8 from Aug 2018]
2026.04.04 04:32:08 UTC
EPSU - External Load Fault
1. Possible Causes
- POWER-EMERGENCY SUPPLY [10WL]
- ESCAPE SLIDE FWD L [7500MM]
- ESCAPE SLIDE FWD R [7501MM]
- wiring
- PROX SW-HANDLE, R FWD ESC SLIDE [4WN2]
- PROX SW-HANDLE, R FWD PAX/CREW DOOR [13WV2]
- PROX SW-HANDLE, L FWD ESC SLIDE [4WN1]
- PROX SW-HANDLE, L FWD PAX/CREW DOOR [13WV1]
- PROXIMITY SWITCH 4WN1
- PROXIMITY SWITCH 13WV1
- PROXIMITY SWITCH 4WN2
- PROXIMITY SWITCH 13WV2
- EPSU [11WL]
lamp(s) - LIGHT-FWD EMER, OVERWING [61WL]
- LIGHT-AFT EMER, OVERWING [63WL]
- ESCAPE SLIDE OFFWING L [7504MM]
- PROX SW-HANDLE, L AFT EMER EXIT ESC SLIDE [6WN1]
- PROX SW-HANDLE FLAP, L AFT EMER EXIT [21WV1]
- PROXIMITY SWITCH 6WN1
- PROXIMITY SWITCH 21WV1
- EPSU [12WL]
- LIGHT-FWD EMER, OVERWING [60WL]
- LIGHT-AFT EMER, OVERWING [62WL]
- ESCAPE SLIDE OFFWING R [7505MM]
- PROX SW-HANDLE, R AFT EMER EXIT ESC SLIDE [6WN2]
- PROX SW-HANDLE FLAP, R AFT EMER EXIT [21WV2]
- PROXIMITY SWITCH 6WN2
- PROXIMITY SWITCH 21WV2
- EPSU [13WL]
- ESCAPE SLIDE AFT L [7502MM]
- ESCAPE SLIDE AFT R [7503MM]
- PROX SW-HANDLE, R AFT ESC SLIDE [7WN2]
- PROX SW-HANDLE, R AFT PAX/CREW DOOR [17WV2]
- PROX SW-HANDLE, L AFT ESC SLIDE [7WN1]
- PROX SW-HANDLE, L AFT PAX/CREW DOOR [17WV1]
- PROXIMITY SWITCH 7WN1
- PROXIMITY SWITCH 17WV1
- PROXIMITY SWITCH 7WN2
- PROXIMITY SWITCH 17WV2
A. Referenced Information
| REFERENCE | DESIGNATION |
|---|---|
| TSM TASK 33-51-00-810-807-A | EPSU - Internal Load Fault Message |
| AMM 25-62-42-000-001 | Offwing Escape-Slide - Removal |
| AMM 25-62-42-400-001 | Offwing Escape-Slide - Installation |
| AMM 25-62-44-000-002 | Removal of the Left-Hand Escape-Slide Pack-Assembly |
| AMM 25-62-44-400-006 | Installation of the Left-Hand Escape-Slide Pack-Assembly |
| AMM 33-51-00-710-001 | Operational Test of the Emergency Lights |
| AMM 33-51-00-710-006 | Operational Test of Emergency Lights not with CIDS |
| AMM 33-51-00-720-001 | Check of the Door Switch Power Supply from the Emer. Light System and of the Door Switch Operation for the Exterior Lights |
| ASM 335101 | |
| ASM 335102 | |
| ASM 335104 | |
| AWM 335104 | |
| AMM 33-51-15-000-001 | Removal of the Emergency Overwing Lights |
| AMM 33-51-15-400-001 | Installation of the Emergency Overwing Lights 60WL |
| AMM 33-51-38-000-001 | Removal of the Emergency Power-Supply Unit (EPSU) |
| AMM 33-51-38-400-001 | Installation of the Emergency Power-Supply Unit (EPSU) |
| AMM 52-71-11-000-001 | Removal of the Proximity Switches of the Passenger/Crew Doors |
| AMM 52-71-11-400-001 | Installation of the Proximity Switches of the Passenger/Crew Door |
| AMM 52-71-13-000-001 | Removal of the Proximity Switches |
| AMM 52-71-13-400-001 | Installation of the Proximity Switches |
| AMM 52-73-11-000-001 | Removal of the Proximity Switches of the FWD Passenger/Crew Doors |
| AMM 52-73-11-000-002 | Removal of the Proximity Switches of the Aft Passenger/Crew Doors |
| AMM 52-73-11-000-004 | Removal of the Proximity Switches of the Aft Emergency Exits |
| AMM 52-73-11-400-001 | Installation of the Proximity Switches of the FWD Passenger/Crew Doors |
| AMM 52-73-11-400-002 | Installation of the Proximity Switches of the Aft Passenger/Crew Doors |
| AMM 52-73-11-400-004 | Installation of the Proximity Switches of the Aft Emergency Exits |
CAUTION:
DO NOT USE THE TEACH-IN PROCEDURE AS AN ALTERNATIVE FOR TROUBLESHOOTING. A TEACH-IN PROCEDURE IS NOT A RESET PROCEDURE. BEFORE YOU DO A TEACH-IN PROCEDURE, MAKE SURE THAT YOU CORRECTED ALL FAILURES. IF YOU DO NOT OBEY THIS, FAILURES CAN CAUSE A MALFUNCTION OF THE CABIN EMERGENCY LIGHTING SYSTEM.
Subtask 33-51-00-710-064-A ** ON A/C NOT FOR ALL 4. Fault IsolationSubtask 33-51-00-810-074-A ** ON A/C NOT FOR ALL
A. If the test gives a different maintenance message, do the trouble shooting procedure related to the maintenance message.
Subtask 33-51-00-810-057-B ** ON A/C NOT FOR ALL B. If the operational test gives the maintenance message
EPSU EXT LOAD FWD L:
Subtask 33-51-00-810-087-D ** ON A/C NOT FOR ALL EPSU EXT LOAD FWD L:
- do the operational test of the emergency lights not with CIDS AMM 33-51-00-710-006.
- replace the POWER-EMERGENCY SUPPLY [10WL] AMM 33-51-38-000-001 and AMM 33-51-38-400-001.
NOTE: A fault in one of the two forward escape slides can cause the LED to come on.
NOTE: For tests, it is necessary to use one of the items of equipment that follow:
(a) Do the procedures that follow: - A connector with four lamps (6V, 0.2 amps) in parallel
- A connector with a 7.5 ohm, 5 watt resistor
- A serviceable escape slide.
- remove the ESCAPE SLIDE FWD L [7500MM] as necessary to get access to the electrical connector AMM 25-62-44-000-002.
NOTE: The step that follows gives the connection of the escape slide only. With one of the other possible items the procedure is the same.
- connect a serviceable escape slide with the adapter cable to the pins A and B of the connector 2871.
- remove the used ESCAPE SLIDE FWD L [7500MM] fully AMM 25-62-44-000-002.
- install a serviceable escape slide AMM 25-62-44-400-006.
- connect the ESCAPE SLIDE FWD L [7500MM] electrically only.
- remove the ESCAPE SLIDE FWD R [7501MM] as necessary to get access to the electrical connector AMM 25-62-44-000-002.
NOTE: The step that follows gives the connection of the escape slide only. With one of the other possible items, the procedure is the same.
- connect a serviceable escape slide with the adapter cable to the pins A and B of the connector 2870.
- remove the used ESCAPE SLIDE FWD R [7501MM] fully AMM 25-62-44-000-002.
- install a serviceable escape slide AMM 25-62-44-400-006.
- install the used ESCAPE SLIDE FWD L [7500MM] AMM 25-62-44-400-006.
- do a check and repair the wiring between:
escape slide connector 2870VC pin A and EPSU (10WL) pin F,
escape slide connector 2870VC pin B and GND,
PROX SW-HANDLE, R FWD ESC SLIDE [4WN2] pin E and EPSU (10WL) pin S,
PROX SW-HANDLE, R FWD ESC SLIDE [4WN2] pin F and GND,
PROX SW-HANDLE, R FWD PAX/CREW DOOR [13WV2] pin E and EPSU (10WL) pin <K,
PROX SW-HANDLE, R FWD PAX/CREW DOOR [13WV2] pin F and GND
ASM 335101 and AWM 335104.
- install the used ESCAPE SLIDE FWD R [7501MM] AMM 25-62-44-400-006.
- install the used ESCAPE SLIDE FWD L [7500MM] AMM 25-62-44-400-006.
- do a check and repair the wiring between:
escape slide connector 2871VC pin A and EPSU (10WL) pin T,
escape slide connector 2871VC pin B and GND,
PROX SW-HANDLE, L FWD ESC SLIDE [4WN1] pin E and EPSU (10WL) pin C,
PROX SW-HANDLE, L FWD ESC SLIDE [4WN1] pin F and GND,
PROX SW-HANDLE, L FWD PAX/CREW DOOR [13WV1] pin E and EPSU (10WL) pin D,
PROX SW-HANDLE, L FWD PAX/CREW DOOR [13WV1] pin F and GND
ASM 335101 and AWM 335104. - install the used ESCAPE SLIDE FWD L [7500MM] AMM 25-62-44-400-006.
- install the used ESCAPE SLIDE FWD R [7501MM] AMM 25-62-44-400-006.
- replace the PROX SW-HANDLE, L FWD ESC SLIDE [4WN1] AMM 52-73-11-000-001 and AMM 52-73-11-400-001.
- replace the PROX SW-HANDLE, L FWD PAX/CREW DOOR [13WV1] AMM 52-71-11-000-001 and AMM 52-71-11-400-001.
- replace the PROX SW-HANDLE, R FWD ESC SLIDE [4WN2] AMM 52-73-11-000-001 and AMM 52-73-11-400-001.
- replace the PROX SW-HANDLE, R FWD PAX/CREW DOOR [13WV2] AMM 52-71-11-000-001 and AMM 52-71-11-400-001.
NOTE: A fault in one of the two forward escape slides can cause the LED to come on.
NOTE: For tests, it is necessary to use one of the items of equipment that follow:
(a) Do the procedures that follow: - A connector with four lamps (6V, 0.2 amps) in parallel
- A connector with a 7.5 ohm, 5 watt resistor
- A serviceable escape slide.
- remove the ESCAPE SLIDE FWD L [7500MM] AMM 25-62-44-000-002.
- connect a serviceable escape slide electrically only.
- install a serviceable escape slide AMM 25-62-44-400-006.
- connect the removed ESCAPE SLIDE FWD L [7500MM] electrically only.
- remove the ESCAPE SLIDE FWD R [7501MM] AMM 25-62-44-000-002.
- connect a serviceable escape slide electrically only.
- install a serviceable escape slide AMM 25-62-44-400-006.
- install the used ESCAPE SLIDE FWD L [7500MM] AMM 25-62-44-400-006.
- do a check and repair the wiring between:
escape slide connector 2870VC pin A and EPSU (10WL) pin F,
escape slide connector 2870VC pin B and GND,
PROX SW-HANDLE, R FWD ESC SLIDE [4WN2] pin E and EPSU (10WL) pin S,
PROX SW-HANDLE, R FWD ESC SLIDE [4WN2] pin F and GND,
PROX SW-HANDLE, R FWD PAX/CREW DOOR [13WV2] pin E and EPSU (10WL) pin <K,
PROX SW-HANDLE, R FWD PAX/CREW DOOR [13WV2] pin F and GND
ASM 335101 and AWM 335104.
- install the removed ESCAPE SLIDE FWD R [7501MM] again AMM 25-62-44-400-006.
- install the used ESCAPE SLIDE FWD L [7500MM] AMM 25-62-44-400-006.
- do a check and repair the wiring between:
escape slide connector 2871VC pin A and EPSU (10WL) pin T,
escape slide connector 2871VC pin B and GND,
PROX SW-HANDLE, L FWD ESC SLIDE [4WN1] pin E and EPSU (10WL) pin C,
PROX SW-HANDLE, L FWD ESC SLIDE [4WN1] pin F and GND,
PROX SW-HANDLE, L FWD PAX/CREW DOOR [13WV1] pin E and EPSU (10WL) pin D,
PROX SW-HANDLE, L FWD PAX/CREW DOOR [13WV1] pin F and GND
ASM 335101 and AWM 335104. - install the used ESCAPE SLIDE FWD L [7500MM] AMM 25-62-44-400-006.
- install the removed ESCAPE SLIDE FWD R [7501MM] again AMM 25-62-44-400-006.
- replace the PROX SW-HANDLE, L FWD ESC SLIDE [4WN1] AMM 52-73-11-000-001 and AMM 52-73-11-400-001.
- replace the PROX SW-HANDLE, L FWD PAX/CREW DOOR [13WV1] AMM 52-71-11-000-001 and AMM 52-71-11-400-001.
- replace the PROX SW-HANDLE, R FWD ESC SLIDE [4WN2] AMM 52-73-11-000-001 and AMM 52-73-11-400-001.
- replace the PROX SW-HANDLE, R FWD PAX/CREW DOOR [13WV2] AMM 52-71-11-000-001 and AMM 52-71-11-400-001.
- replace the POWER-EMERGENCY SUPPLY [10WL] AMM 33-51-38-000-001 and AMM 33-51-38-400-001.
- do a check of all connected exterior lights and proximity switches for a short-circuit and replace if necessary ASM 335101 and ASM 335104,
- if you find one or more defective exterior lights or proximity switches, replace the POWER-EMERGENCY SUPPLY [10WL] AMM 33-51-38-000-001 AMM 33-51-38-400-001.
- do a check for a short to ground and repair the wiring if necessary ASM 335101 and ASM 335104:
from EPSU (10WL) pin F to the connector(s) of the related signs and lights,
from EPSU (10WL) pin T to the connector(s) of the related signs and lights,
from EPSU (10WL) pin C to the connector of the PROXIMITY SWITCH 4WN1 ,
from EPSU (10WL) pin D to the connector of the PROXIMITY SWITCH 13WV1 ,
from EPSU (10WL) pin S to the connector of the PROXIMITY SWITCH 4WN2 ,
from EPSU (10WL) pin <K to the connector of the PROXIMITY SWITCH 13WV2 ,
from EPSU (10WL) pin <Q to the connector(s) of the proximity switches, - if you find a short to ground in the wiring, replace the POWER-EMERGENCY SUPPLY [10WL] AMM 33-51-38-000-001 and AMM 33-51-38-400-001.
- do the trouble shooting procedure EPSU - Internal Load Fault Message (Ref. TSM TASK 33-51-00-810-807).
C. If the operational test gives the maintenance message
EPSU EXT LOAD EMER L:
(a) If one or more lamps of the LIGHT-FWD EMER, OVERWING (61WL) and the LIGHT-AFT EMER, OVERWING (63WL) do not come on:
Subtask 33-51-00-810-088-D ** ON A/C NOT FOR ALL EPSU EXT LOAD EMER L:
- do the operational test of the emergency lights not with CIDS AMM 33-51-00-710-006.
- replace the EPSU [11WL] AMM 33-51-38-000-001 and AMM 33-51-38-400-001.
(a) If one or more lamps of the LIGHT-FWD EMER, OVERWING (61WL) and the LIGHT-AFT EMER, OVERWING (63WL) do not come on:
- replace the
lamp(s) AMM 33-51-15-000-001 and AMM 33-51-15-400-001.
- replace the related LIGHT-FWD EMER, OVERWING [61WL] and/or LIGHT-AFT EMER, OVERWING [63WL] AMM 33-51-15-000-001 and AMM 33-51-15-400-001.
- remove the ESCAPE SLIDE OFFWING L [7504MM] as necessary to get access to the electrical connector AMM 25-62-42-000-001.
- connect a serviceable escape slide with the adapter cable to the aircraft.
- do the operational test of the emergency lights not with CIDS AMM 33-51-00-710-006.
- remove the old ESCAPE SLIDE OFFWING L [7504MM] fully AMM 25-62-42-000-001.
- install a serviceable escape slide AMM 25-62-42-400-001.
- do a check and repair the wiring between:
escape slide connector 7531VC pin A and EPSU (11WL) pin T,
escape slide connector 7531VC pin B and GND,
LIGHT-FWD EMER, OVERWING [61WL] connector A/B and EPSU (11WL) pin T,
LIGHT-FWD EMER, OVERWING [61WL] connector A/A and GND,
LIGHT-FWD EMER, OVERWING [61WL] connector A/C and GND,
LIGHT-AFT EMER, OVERWING [63WL] connector A/B and EPSU (11WL) pin F,
LIGHT-AFT EMER, OVERWING [63WL] connector A/A and GND,
LIGHT-AFT EMER, OVERWING [63WL] connector A/C and GND,
PROX SW-HANDLE, L AFT EMER EXIT ESC SLIDE [6WN1] pin E and EPSU (11WL) pin S,
PROX SW-HANDLE, L AFT EMER EXIT ESC SLIDE [6WN1] pin F and GND,
PROX SW-HANDLE FLAP, L AFT EMER EXIT [21WV1] pin E and EPSU (11WL) pin <K,
PROX SW-HANDLE FLAP, L AFT EMER EXIT [21WV1] pin F and GND
ASM 335102 and AWM 335104. - install the old ESCAPE SLIDE OFFWING L [7504MM] AMM 25-62-42-400-001.
- replace the PROX SW-HANDLE, L AFT EMER EXIT ESC SLIDE [6WN1] AMM 52-73-11-000-004 and AMM 52-73-11-400-004.
- replace the PROX SW-HANDLE FLAP, L AFT EMER EXIT [21WV1] AMM 52-71-13-000-001 and AMM 52-71-13-400-001.
- remove the ESCAPE SLIDE OFFWING L [7504MM] AMM 25-62-42-000-001.
- connect a serviceable escape slide electrically only.
- do the operational test of the emergency lights not with CIDS AMM 33-51-00-710-006.
- install a serviceable escape slide AMM 25-62-42-400-001.
- do a check and repair the wiring between:
escape slide connector 7531VC pin A and EPSU (11WL) pin T,
escape slide connector 7531VC pin B and GND,
LIGHT-FWD EMER, OVERWING [61WL] connector A/B and EPSU (11WL) pin T,
LIGHT-FWD EMER, OVERWING [61WL] connector A/A and GND,
LIGHT-FWD EMER, OVERWING [61WL] connector A/C and GND,
LIGHT-AFT EMER, OVERWING [63WL] connector A/B and EPSU (11WL) pin F,
LIGHT-AFT EMER, OVERWING [63WL] connector A/A and GND,
LIGHT-AFT EMER, OVERWING [63WL] connector A/C and GND,
PROX SW-HANDLE, L AFT EMER EXIT ESC SLIDE [6WN1] pin E and EPSU (11WL) pin S,
PROX SW-HANDLE, L AFT EMER EXIT ESC SLIDE [6WN1] pin F and GND,
PROX SW-HANDLE FLAP, L AFT EMER EXIT [21WV1] pin E and EPSU (11WL) pin <K,
PROX SW-HANDLE FLAP, L AFT EMER EXIT [21WV1] pin F and GND
ASM 335102 and AWM 335104. - install the removed ESCAPE SLIDE OFFWING L [7504MM] again AMM 25-62-42-400-001.
- replace the PROX SW-HANDLE, L AFT EMER EXIT ESC SLIDE [6WN1] AMM 52-73-11-000-004 and AMM 52-73-11-400-004.
- replace the PROX SW-HANDLE FLAP, L AFT EMER EXIT [21WV1] AMM 52-71-13-000-001 and AMM 52-71-13-400-001.
- replace the EPSU [11WL] AMM 33-51-38-000-001 and AMM 33-51-38-400-001.
- check all connected exterior lights and proximity switches for a short-circuit and replace if necessary ASM 335101 and ASM 335104,
- if you find one or more defective exterior lights or proximity switches, replace the EPSU [11WL] AMM 33-51-38-000-001 AMM 33-51-38-400-001.
- do a check for a short to ground an repair the wiring if necessary ASM 335101 and ASM 335104:
from EPSU (11WL) pin F to the connector(s) of the related signs and lights,
from EPSU (11WL) pin T to the connector(s) of the related signs and lights,
from EPSU (11WL) pin S to the connector of the PROXIMITY SWITCH 6WN1 ,
from EPSU (11WL) pin <K to the connector of the PROXIMITY SWITCH 21WV1 ,
from EPSU (11WL) pin <Q to the connector(s) of the proximity switches, - if you find a short to ground in the wiring, replace the EPSU [11WL] AMM 33-51-38-000-001 and AMM 33-51-38-400-001.
- do the trouble shooting procedure EPSU - Internal Load Fault Message (Ref. TSM TASK 33-51-00-810-807).
D. If the operational test gives the maintenance message
EPSU EXT LOAD EMER R:
(a) If one or more lamps of the LIGHT-FWD EMER, OVERWING (60WL) and the LIGHT-AFT EMER, OVERWING (62WL) do not come on:
Subtask 33-51-00-810-086-C ** ON A/C NOT FOR ALL EPSU EXT LOAD EMER R:
- do the operational test of the emergency lights not with CIDS AMM 33-51-00-710-006.
- replace the EPSU [12WL] AMM 33-51-38-000-001 and AMM 33-51-38-400-001.
(a) If one or more lamps of the LIGHT-FWD EMER, OVERWING (60WL) and the LIGHT-AFT EMER, OVERWING (62WL) do not come on:
- replace the
lamp(s) AMM 33-51-15-000-001 and AMM 33-51-15-400-001.
- replace the related LIGHT-FWD EMER, OVERWING [60WL] and/or LIGHT-AFT EMER, OVERWING [62WL] AMM 33-51-15-000-001 and AMM 33-51-15-400-001.
- remove the ESCAPE SLIDE OFFWING R [7505MM] as necessary to get access to the electrical connector AMM 25-62-42-000-001.
- connect a serviceable escape slide with the adapter cable to the aircraft.
- do the operational test of the emergency lights not with CIDS AMM 33-51-00-710-006.
- remove the old ESCAPE SLIDE OFFWING R [7505MM] fully AMM 25-62-42-000-001.
- install a serviceable escape slide AMM 25-62-42-400-001.
- do a check and repair the wiring between:
escape slide connector 7532VC pin A and EPSU (12WL) pin T,
escape slide connector 7532VC pin B and GND,
LIGHT-FWD EMER, OVERWING [60WL] connector A/B and EPSU (12WL) pin T,
LIGHT-FWD EMER, OVERWING [60WL] connector A/A and GND,
LIGHT-FWD EMER, OVERWING [60WL] connector A/C and GND,
LIGHT-AFT EMER, OVERWING [62WL] connector A/B and EPSU (12WL) pin F,
LIGHT-AFT EMER, OVERWING [62WL] connector A/A and GND,
LIGHT-AFT EMER, OVERWING [62WL] connector A/C and GND,
PROX SW-HANDLE, R AFT EMER EXIT ESC SLIDE [6WN2] pin E and EPSU (12WL) pin S,
PROX SW-HANDLE, R AFT EMER EXIT ESC SLIDE [6WN2] pin F and GND,
PROX SW-HANDLE FLAP, R AFT EMER EXIT [21WV2] pin E and EPSU (12WL) pin <K,
PROX SW-HANDLE FLAP, R AFT EMER EXIT [21WV2] pin F and GND
ASM 335102 and AWM 335104. - install the old ESCAPE SLIDE OFFWING R [7505MM] AMM 25-62-42-400-001.
- replace the PROX SW-HANDLE, R AFT EMER EXIT ESC SLIDE [6WN2] AMM 52-73-11-000-004 and AMM 52-73-11-400-004.
- replace the PROX SW-HANDLE FLAP, R AFT EMER EXIT [21WV2] AMM 52-71-13-000-001 and AMM 52-71-13-400-001.
- remove the ESCAPE SLIDE OFFWING R [7505MM] AMM 25-62-42-000-001.
- connect a serviceable escape slide electrically only.
- do the operational test of the emergency lights not with CIDS AMM 33-51-00-710-006.
- install a serviceable escape slide AMM 25-62-42-400-001.
- do a check and repair the wiring between:
escape slide connector 7532VC pin A and EPSU (12WL) pin T,
escape slide connector 7532VC pin B and GND,
LIGHT-FWD EMER, OVERWING [60WL] connector A/B and EPSU (12WL) pin T,
LIGHT-FWD EMER, OVERWING [60WL] connector A/A and GND,
LIGHT-FWD EMER, OVERWING [60WL] connector A/C and GND,
LIGHT-AFT EMER, OVERWING [62WL] connector A/B and EPSU (12WL) pin F,
LIGHT-AFT EMER, OVERWING [62WL] connector A/A and GND,
LIGHT-AFT EMER, OVERWING [62WL] connector A/C and GND,
PROX SW-HANDLE, R AFT EMER EXIT ESC SLIDE [6WN2] pin E and EPSU (12WL) pin S,
PROX SW-HANDLE, R AFT EMER EXIT ESC SLIDE [6WN2] pin F and GND,
PROX SW-HANDLE FLAP, R AFT EMER EXIT [21WV2] pin E and EPSU (12WL) pin <K,
PROX SW-HANDLE FLAP, R AFT EMER EXIT [21WV2] pin F and GND
ASM 335102 and AWM 335104. - install the removed ESCAPE SLIDE OFFWING R [7505MM] again AMM 25-62-42-400-001.
- replace the PROX SW-HANDLE, R AFT EMER EXIT ESC SLIDE [6WN2] AMM 52-73-11-000-004 and AMM 52-73-11-400-004.
- replace the PROX SW-HANDLE FLAP, R AFT EMER EXIT [21WV2] AMM 52-71-13-000-001 and AMM 52-71-13-400-001.
- replace the EPSU [12WL] AMM 33-51-38-000-001 and AMM 33-51-38-400-001.
- check all connected exterior lights and proximity switches for a short-circuit and replace if necessary ASM 335101 and ASM 335104,
- if you find one or more defective exterior lights or proximity switches, replace the EPSU [12WL] AMM 33-51-38-000-001 AMM 33-51-38-400-001.
- do a check for a short to ground an repair the wiring if necessary ASM 335101 and ASM 335104:
from EPSU (12WL) pin F to the connector(s) of the related signs and lights,
from EPSU (12WL) pin T to the connector(s) of the related signs and lights,
from EPSU (12WL) pin S to the connector of the PROXIMITY SWITCH 6WN2 ,
from EPSU (12WL) pin <K to the connector of the PROXIMITY SWITCH 21WV2 ,
from EPSU (12WL) pin <Q to the connector(s) of the proximity switches, - if you find a short to ground in the wiring, replace the EPSU [12WL] AMM 33-51-38-000-001 and AMM 33-51-38-400-001.
- do the trouble shooting procedure EPSU - Internal Load Fault Message (Ref. TSM TASK 33-51-00-810-807).
E. If the operational test gives the maintenance message
EPSU EXT LOAD AFT L:
Subtask 33-51-00-710-065-A ** ON A/C NOT FOR ALL EPSU EXT LOAD AFT L:
- do the operational test of the emergency lights not with CIDS AMM 33-51-00-710-006.
- replace the EPSU [13WL] AMM 33-51-38-000-001 and AMM 33-51-38-400-001.
NOTE: A fault in one of the two aft escape slides can cause the LED to come on.
(a) Do the subsequent procedures: - remove the ESCAPE SLIDE AFT L [7502MM] as necessary to get access to the electrical connector AMM 25-62-44-000-002.
- connect a serviceable escape slide with the adapter cable to the aircraft.
- remove the old ESCAPE SLIDE AFT L [7502MM] fully AMM 25-62-44-000-002.
- install a serviceable escape slide AMM 25-62-44-400-006.
- connect the ESCAPE SLIDE AFT L [7502MM] electrically only.
- remove the ESCAPE SLIDE AFT R [7503MM] as necessary to get access to the electrical connector AMM 25-62-44-000-002.
- connect a serviceable escape slide with the adapter cable to the aircraft.
- remove the old ESCAPE SLIDE AFT R [7503MM] fully AMM 25-62-44-000-002.
- install a serviceable escape slide AMM 25-62-44-400-006.
- install the old ESCAPE SLIDE AFT L [7502MM] AMM 25-62-44-400-006.
- do a check and repair the wiring between:
escape slide connector 2872VC pin A and EPSU (13WL) pin F,
escape slide connector 2872VC pin B and GND,
PROX SW-HANDLE, R AFT ESC SLIDE [7WN2] pin E and EPSU (13WL) pin S,
PROX SW-HANDLE, R AFT ESC SLIDE [7WN2] pin F and GND,
PROX SW-HANDLE, R AFT PAX/CREW DOOR [17WV2] pin E and EPSU (13WL) pin <K,
PROX SW-HANDLE, R AFT PAX/CREW DOOR [17WV2] pin F and GND
ASM 335102 and AWM 335104.
- install the old ESCAPE SLIDE AFT R [7503MM] AMM 25-62-44-400-006.
- install the old ESCAPE SLIDE AFT L [7502MM] AMM 25-62-44-400-006.
- do a check and repair the wiring between:
escape slide connector 2873VC pin A and EPSU (13WL) pin T,
escape slide connector 2873VC pin B and GND,
PROX SW-HANDLE, L AFT ESC SLIDE [7WN1] pin E and EPSU (13WL) pin C,
PROX SW-HANDLE, L AFT ESC SLIDE [7WN1] pin F and GND,
PROX SW-HANDLE, L AFT PAX/CREW DOOR [17WV1] pin E and EPSU (13WL) pin D,
PROX SW-HANDLE, L AFT PAX/CREW DOOR [17WV1] pin F and GND
ASM 335102 and AWM 335104. - install the old ESCAPE SLIDE AFT L [7502MM] AMM 25-62-44-400-006.
- install the old ESCAPE SLIDE AFT R [7503MM] AMM 25-62-44-400-006.
- replace the PROX SW-HANDLE, L AFT ESC SLIDE [7WN1] AMM 52-73-11-000-002 and AMM 52-73-11-400-002.
- replace the PROX SW-HANDLE, L AFT PAX/CREW DOOR [17WV1] AMM 52-71-11-000-001 and AMM 52-71-11-400-001.
- replace the PROX SW-HANDLE, R AFT ESC SLIDE [7WN2] AMM 52-73-11-000-002 and AMM 52-73-11-400-002.
- replace the PROX SW-HANDLE, R AFT PAX/CREW DOOR [17WV2] AMM 52-71-11-000-001 and AMM 52-71-11-400-001.
NOTE: A fault in one of the two aft escape slides can cause the LED to come on.
(a) Do the subsequent procedures: - remove the ESCAPE SLIDE AFT L [7502MM] AMM 25-62-44-000-002.
- connect a serviceable escape slide electrically only.
- install a serviceable escape slide AMM 25-62-44-400-006.
- connect the removed ESCAPE SLIDE AFT L [7502MM] electrically only.
- remove the ESCAPE SLIDE AFT R [7503MM] AMM 25-62-44-000-002.
- connect a serviceable escape slide electrically only.
- install a serviceable escape slide AMM 25-62-44-400-006.
- install the old ESCAPE SLIDE AFT L [7502MM] AMM 25-62-44-400-006.
- do a check and repair the wiring between:
escape slide connector 2872VC pin A and EPSU (13WL) pin F,
escape slide connector 2872VC pin B and GND,
PROX SW-HANDLE, R AFT ESC SLIDE [7WN2] pin E and EPSU (13WL) pin S,
PROX SW-HANDLE, R AFT ESC SLIDE [7WN2] pin F and GND,
PROX SW-HANDLE, R AFT PAX/CREW DOOR [17WV2] pin E and EPSU (13WL) pin <K,
PROX SW-HANDLE, R AFT PAX/CREW DOOR [17WV2] pin F and GND
ASM 335102 and AWM 335104.
- install the removed ESCAPE SLIDE AFT R [7503MM] again AMM 25-62-44-400-006.
- install the old ESCAPE SLIDE AFT L [7502MM] AMM 25-62-44-400-006.
- do a check and repair the wiring between:
escape slide connector 2873VC pin A and EPSU (13WL) pin T,
escape slide connector 2873VC pin B and GND,
PROX SW-HANDLE, L AFT ESC SLIDE [7WN1] pin E and EPSU (13WL) pin C,
PROX SW-HANDLE, L AFT ESC SLIDE [7WN1] pin F and GND,
PROX SW-HANDLE, L AFT PAX/CREW DOOR [17WV1] pin E and EPSU (13WL) pin D,
PROX SW-HANDLE, L AFT PAX/CREW DOOR [17WV1] pin F and GND
ASM 335102 and AWM 335104. - install the old ESCAPE SLIDE AFT L [7502MM] AMM 25-62-44-400-006.
- install the removed ESCAPE SLIDE AFT R [7503MM] again AMM 25-62-44-400-006.
- replace the PROX SW-HANDLE, L AFT ESC SLIDE [7WN1] AMM 52-73-11-000-002 and AMM 52-73-11-400-002.
- replace the PROX SW-HANDLE, L AFT PAX/CREW DOOR [17WV1] AMM 52-71-11-000-001 and AMM 52-71-11-400-001.
- replace the PROX SW-HANDLE, R AFT ESC SLIDE [7WN2] AMM 52-73-11-000-002 and AMM 52-73-11-400-002.
- replace the PROX SW-HANDLE, R AFT PAX/CREW DOOR [17WV2] AMM 52-71-11-000-001 and AMM 52-71-11-400-001.
- replace the EPSU [13WL] AMM 33-51-38-000-001 and AMM 33-51-38-400-001.
- check all connected exterior lights and proximity switches for a short-circuit and replace if necessary ASM 335101 and ASM 335104,
- if you find one or more defective exterior lights or proximity switches, replace the EPSU [13WL] AMM 33-51-38-000-001 AMM 33-51-38-400-001.
- do a check for a short to ground an repair the wiring if necessary ASM 335101 and ASM 335104:
from EPSU (13WL) pin F to the connector(s) of the related signs and lights,
from EPSU (13WL) pin T to the connector(s) of the related signs and lights,
from EPSU (13WL) pin C to the connector of the PROXIMITY SWITCH 7WN1 ,
from EPSU (13WL) pin D to the connector of the PROXIMITY SWITCH 17WV1 ,
from EPSU (13WL) pin S to the connector of the PROXIMITY SWITCH 7WN2 ,
from EPSU (13WL) pin <K to the connector of the PROXIMITY SWITCH 17WV2 ,
from EPSU (13WL) pin <Q to the connector(s) of the proximity switches, - if you find a short to ground in the wiring, replace the EPSU [13WL] AMM 33-51-38-000-001 and AMM 33-51-38-400-001.
- do the trouble shooting procedure EPSU - Internal Load Fault Message (Ref. TSM TASK 33-51-00-810-807).
F. Do the test as given in Para. 3.A.
5. Close-upSubtask 33-51-00-860-071-A ** ON A/C NOT FOR ALL
A. Put the aircraft back to its initial configuration.