Failure of the Ground Power Control Unit

TASK 24-40-00-810-805-A
Failure of the Ground Power Control Unit

1. Possible Causes

wiring
GPCU [1XG]
C/B-ELEC/GPCU [7XG]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
TSM TASK 24-00-00-810-803-A	Circuit Breaker Tripped and/or C/B TRIPPED Warning
AMM 24-41-00-740-004	Operational Check of the GPCU via the CFDS
AMM 24-41-00-861-002	Energize the Aircraft Electrical Circuits from the External Power
AMM 24-41-00-862-002	De-energize the Aircraft Electrical Circuits Supplied from the External Power
ASM 244101
AMM 24-41-34-000-001	Removal of the Ground Power Control Unit (GPCU)
AMM 24-41-34-400-001	Installation of the Ground Power Control Unit (GPCU)

3. Fault Confirmation
Subtask 24-40-00-860-058-A ** ON A/C NOT FOR ALL

A. Job Set-Up
(1) Aircraft Maintenance Configuration
(a) Energize the aircraft electrical circuits
AMM 24-41-00-861-002

Subtask 24-40-00-740-054-A ** ON A/C NOT FOR ALL

B. Test
Do the operational check of the GPCU with the CFDS AMM 24-41-00-740-004.

4. Fault Isolation
Subtask 24-40-00-810-054-A ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message GPCU and, on the panel 108VU, the EXT PWR light is not on:

Do a check of the status of the ELEC/GPCU circuit breaker (7XG):

(1) If the circuit breaker is closed:

Do a check for 28VDC at the pin B/15A of the GPCU.

(a) If there is not 28VDC:

Do a check and repair the wiring between the circuit breaker (7XG) and the pin B/15A of the GPCU ASM 244101.

(b) If there is 28VDC:

Replace the GPCU [1XG] AMM 24-41-34-000-001 and AMM 24-41-34-400-001.

(2) If the circuit breaker is open:

Do the procedure (Ref. TSM TASK 24-00-00-810-803).

(a) If the fault continues:

Replace the C/B-ELEC/GPCU [7XG] .

Subtask 24-40-00-700-059-A ** ON A/C NOT FOR ALL

B. Make sure that the aircraft electrical circuits operate correctly in ground configuration.
(1) Energize the aircraft electrical circuits from the external power AMM 24-41-00-861-002.
(2) De-energize the aircraft electrical circuits from the external power AMM 24-41-00-862-002.

5. Close-up
Subtask 24-40-00-860-059-A ** ON A/C NOT FOR ALL

A. Put the aircraft back to its initial configuration.
(1) On the ECAM control panel, set the UPPER DISPLAY and LOWER DISPLAY potentiometers to OFF.
(2) De-energize the aircraft electrical circuits
AMM 24-41-00-862-002

[Rev.8 from Aug 2018] 2026.04.04 04:26:52 UTC