The Battery of EPSU 14WL has an Overtemperature Condition

TASK 33-51-00-810-866-A
The Battery of EPSU 14WL has an Overtemperature Condition

1. Possible Causes

battery of EPSU 14WL
EPSU [14WL]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 33-51-00-710-003	Check of the Battery Capacity
AMM 33-51-38-000-001	Removal of the Emergency Power-Supply Unit (EPSU)
AMM 33-51-38-000-002	Removal of the Battery of the Emergency Power-Supply Unit
AMM 33-51-38-400-001	Installation of the Emergency Power-Supply Unit (EPSU)
AMM 33-51-38-400-002	Installation of the Battery of the Emergency Power-Supply Unit

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 33-51-00-710-177-A ** ON A/C NOT FOR ALL

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

4. Fault Isolation
Subtask 33-51-00-810-191-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 33-51-00-810-192-A ** ON A/C NOT FOR ALL

B. If the operational test gives the maintenance message:
(1) BAT OVERTEMP/EPSU(14WL)MID R:

Make sure that the battery capacity test is completed.
Do the 'Check Battery Capacity' with the 'TEST EMER LIGHT BAT' pushbutton AMM 33-51-00-710-003.

(a) If the fault continues:

Replace the battery of EPSU 14WL AMM 33-51-38-000-002 and AMM 33-51-38-400-002.

(b) If the fault continues:

Replace the EPSU [14WL] AMM 33-51-38-000-001 and AMM 33-51-38-400-001.

Subtask 33-51-00-710-178-A ** ON A/C NOT FOR ALL

C. Do the test given in Para. 3.

5. Close-up
Subtask 33-51-00-860-121-A ** ON A/C NOT FOR ALL

A. Put the aircraft back to its initial configuration.

[Rev.8 from Aug 2018] 2026.04.04 04:32:12 UTC