Fault of the Fire Emergency Stop-Relay 6WF

TASK 26-22-00-810-807-A
Fault of the Fire Emergency Stop-Relay 6WF

1. Possible Causes

FIRE EMERGENCY STOP RELAY (6WF)
ELECTRONIC CONTROL BOX [59KD]
wiring

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 26-22-00-710-002	Operational Test of APU Auto-Fire-Exting. Circuit and the APU LP Fuel-Valve operation using each indiv. motor in turn and Test APU Emerg. Shutdown Circuit
ASM 496101
AMM 49-61-34-000-001	Removal of the Electronic Control Box (ECB) (GTCP 36-300)
AMM 49-61-34-000-002	Removal of the Electronic Control Box (ECB) (APS 3200)
AMM 49-61-34-000-003	Removal of the Electronic Control Box (ECB) (131-9(A))
AMM 49-61-34-400-001	Installation of the Electronic Control Box (ECB) (GTCP 36-300)
AMM 49-61-34-400-002	Installation of the Electronic Control Box (ECB) (APS 3200)
AMM 49-61-34-400-003	Installation of the Electronic Control Box (ECB) (131-9(A))
AMM 49-62-00-710-001	Operational Test of Emergency Shutdown System (with APU SHUT OFF Switch 1KL) (GTCP 36-300)
AMM 49-62-00-710-004	Operational Test of the Emergency Shutdown Circuit (using the APU Shut Off Switch 1KL) (APS 3200)
AMM 49-62-00-710-007	Operational Test of Emergency Shutdown System (with APU SHUT OFF Switch 1KL) (131-9(A))

3. Fault Confirmation
Subtask 26-22-00-710-060-A

A. Do the test of the APU emergency shutdown system with the APU/AUTO EXTING/TEST pushbutton switch.

For GTCP 36-300 APU AMM 49-62-00-710-001.
For APS 3200 APU AMM 49-62-00-710-004.
For 131-9(A) APU AMM 49-62-00-710-007.

4. Fault Isolation
Subtask 26-22-00-810-068-A

A. If the test gives the maintenance message:

FIRE EMERG STOP RLY 6WF

FCN 133 or 134 for APS 3200 APU.
FCN 139 or 140 for GTCP 36-300 or 131-9(A) APU.

replace the FIRE EMERGENCY STOP RELAY (6WF).

(1) If the fault continues:
(a) For GTCP 36-300 APU
1 Replace the ELECTRONIC CONTROL BOX [59KD] AMM 49-61-34-000-001 and AMM 49-61-34-400-001.
(b) For the APS 3200 APU
1 Replace the ELECTRONIC CONTROL BOX [59KD] AMM 49-61-34-000-002 and AMM 49-61-34-400-002.
(c) For the 131-9(A) APU
1 Replace the ELECTRONIC CONTROL BOX [59KD] AMM 49-61-34-000-003 and AMM 49-61-34-400-003.
(2) If the fault continues:

do a check and repair the wiring from the FIRE EMERGENCY STOP RELAY (6WF) A/X2 to the ground. ASM 496101.
do a check and repair the wiring from the ECB (59KD) AB/J14 to the FIRE EMERGENCY STOP RELAY (6WF) A/X1 ASM 496101.

Subtask 26-22-00-710-061-A

B. The APU FIRE EXTINGUISHING PANEL 20VU (p/n 330TS08Y) has a fault. Special operation is necessary. Incorrect operation causes the APU fire extinguisher bottle to discharge. Airbus supplies a new 20VU panel that corrects this fault. See TFU 26.22.00.007 for more data.
(1) Maintenance recommendation:
(a) Before the test:

Pull the CIRCUIT BREAKER 30WF on panel 120VU.

(b) During the test:

Push the APU FIRE TEST BUTTON quickly and fully.
Hold it fully during the test.
Release it quickly.

Close the CIRCUIT BREAKER 30WF on panel 120VU.

(2) Do the operational test of the FIRE EMERGENCY STOP RELAY (6WF) AMM 26-22-00-710-002.

NOTE: After the subsequent flight, make sure that the fault does not continue.

NOTE: Make an entry in the applicable logbook that you must read the APU CLASS 3 FAULTS after the first flight on the subsequent day.

[Rev.8 from Aug 2018] 2026.04.04 04:27:25 UTC