EPSU 12WL does not have a Test Result available

TASK 33-51-00-810-850-A
EPSU 12WL does not have a Test Result available

1. Possible Causes

wiring
EPSU [12WL]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 33-51-00-710-001	Operational Test of the Emergency Lights
AMM 33-51-00-710-003	Check of the Battery Capacity
ASM 335102
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)

3. Fault Confirmation

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 33-51-00-810-154-A ** ON A/C NOT FOR ALL

A. Do the operational test 'Check Battery Capacity' with the MCDU AMM 33-51-00-710-003.

4. Fault Isolation
Subtask 33-51-00-810-155-A ** ON A/C NOT FOR ALL

A. Do the operational test of the emergency lights with the MCDU AMM 33-51-00-710-001.

Subtask 33-51-00-810-156-A ** ON A/C NOT FOR ALL

B. If the operational test gives the maintenance message:
(1) NO TEST RESULT AVAIL/EPSU(12WL)EMER R:

get access to EPSU 12WL AMM 33-51-38-000-001.

(a) Do a check and repair the wiring between:
EPSU 12WL pin -I and DEU-B 300RH6 pin B25.
EPSU 12WL pin -P and DEU-B 300RH6 pin B27.
EPSU 12WL pin X and DEU-B 300RH6 pin B26 ASM 335102.
(b) If the fault continues:

replace the EPSU [12WL] AMM 33-51-38-000-001 and AMM 33-51-38-400-001.

Subtask 33-51-00-710-145-A ** ON A/C NOT FOR ALL

C. Do the test given in Para. 3.

5. Close-up
Subtask 33-51-00-810-157-A ** ON A/C NOT FOR ALL

A. Put the aircraft back to its initial configuration.

[Rev.8 from Aug 2018] 2026.04.04 04:32:11 UTC