APU AUTO EXTING TEST Light Fault

TASK 26-22-00-810-804-A
APU AUTO EXTING TEST Light Fault

1. Possible Causes

RELAY-FLIGHT/GROUND (43WF)
RELAY-AUTO PUSH (34WF)
PUSHBUTTON SWITCH-TEST (31WF)
RELAY- AUTO DISCH (35WF)
EXTING GROUND TEST RELAY (36WF)
EXTING GROUND TEST TIME DELAY RELAY (37WF)
EXTING GROUND TEST RELAY (38WF)
RELAY-AUTO TIME DELAY PUSH (39WF)
wiring
EXITING GROUND TEST TIME DELAY RELAY (37WF)
DIODE (1156VD)
RELAY - TEST (33WF)
EXITING GROUND TEST RELAY (39WF)
PUSHBUTTON SWITCH-RESET (32WF)
RELAY-TEST (33WF)

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
ASM 262202
AMM 32-69-00-740-001	BITE Check of Landing-Gear Control Interface-Unit (LGCIU) With Use of MCDU to Ensure that Continuous BITE is Operative
AMM 33-14-00-710-001	Operational Test of the Lights

3. Fault Confirmation
Subtask 26-22-00-710-053-A

A. Do the operational test of the APU auto-extinguishing system
(1) In the APU/AUTO EXTING section of panel 50VU:
(a) Push the TEST (31WF) pushbutton switch for 3 seconds approximately.
(2) In the APU/AUTO EXTING section of panel 50VU:
(a) Push the RESET (32WF) pushbutton switch.

4. Fault Isolation
Subtask 26-22-00-810-059-A

A. If the OK legend in the APU/AUTO/EXTING TEST p/bsw does not come on during the test:

do the operational test of the annunciator light test system AMM 33-14-00-710-001.

(1) If the fault continues:

do the BITE test of the landing gear AMM 32-69-00-740-001.

(2) If the fault continues:

do a check of the RELAY-FLIGHT/GROUND (43WF) and replace it if necessary ASM 262202.

(3) If the fault continues:

do a check of the RELAY-AUTO PUSH (34WF) and replace it if necessary ASM 262202.

(4) If the fault continues:

do a check of the PUSHBUTTON SWITCH-TEST (31WF) and replace it if necessary ASM 262202.

(5) If the fault continues:

do a check of the RELAY- AUTO DISCH (35WF) and replace it if necessary ASM 262202.

(6) If the fault continues:

do a check of the EXTING GROUND TEST RELAY (36WF) and replace it if necessary ASM 262202.

(7) If the fault continues:

do a check of the EXTING GROUND TEST TIME DELAY RELAY (37WF) and replace it if necessary ASM 262202.

(8) If the fault continues:

do a check of the EXTING GROUND TEST RELAY (38WF) and replace it if necessary ASM 262202.

(9) If the fault continues:

do a check of the RELAY-AUTO TIME DELAY PUSH (39WF) and replace it if necessary ASM 262202.

(10) If the fault continues:

do a check and repair the wiring if necessary between the:
LGCIU (5GA1) connector AA/15B and RELAY (43WF) connector A/X1,
RELAY (43WF) connector A/A2 and RELAY (34WF) connector A/X1,
RELAY (34WF) connector A/X1 an RELAY (39WF)connector A/A2 and A/X1,
RELAY (34WF) connector A/A1 an RELAY (35WF)connector A/A1,
RELAY (34WF) connector A/A2 an RELAY (1LP) connector A/24,
RELAY (1LP) connector A/22 and P/BSW TEST (31WF) connector A/7,
RELAY (43WF) connector A/X2 and GND,
PBSW TEST (31WF) connector A/A3 and C/B (30WF) ASM 262202 and ASM 262202.

Subtask 26-22-00-810-070-A

B. With the Test-tool Box
(1) If the OK legend in the APU/AUTO/EXTING TEST p/bsw does not come on during the test:

do the operational test of the annunciator light test system AMM 33-14-00-710-001.

(a) If the fault continues:

Connect the TEST-TOOL BOX (P/N 77000D262.01000.000) to the socket 1186VC of 130VU via the connection cable.
Do a check of the lights, which are in the front panel of the test-tool box, illuminate:

1 If the P1 light does not illuminate:

do the BITE test of the landing gear AMM 32-69-00-740-001.

. if the test gives a maintenance message, do the troubleshooting procedure related to the maintenance message.

If the fault continues:

. do a check of the RELAY-FLIGHT/GROUND (43WF) and replace it if necessary ASM 262202.

If the fault continues:
. do a check and repair the wiring ASM 262202 if necessary between the:
CONNECTOR 1186VC pin D and RELAY (43WF) connector A/A2.
RELAY (43WF) connector A/A1 and C/B 30WF.
LGCIU (5GA1) connector AA/15B and RELAY (43WF) connector A/X1.
RELAY (43WF) connector A/X2 and GND.

. Push the TEST (31WF) pushbutton switch for 3 seconds approximately.

2 If the P2 light does not illuminate:

do a check fo the EXITING GROUND TEST TIME DELAY RELAY (37WF) and replace it if necessary ASM 262202.

If the fault continues:

. do a check of the EXTING GROUND TEST RELAY (36WF) and replace it if necessary ASM 262202.

If the fault continues:
. do a check of the DIODE (1156VD) and replace it if necessary ASM 262202.
If the fault continues:
. do a check of the EXTING GROUND TEST RELAY (38WF) and replace it if necessary ASM 262202.
If the fault continues:
. do a check of the RELAY - TEST (33WF) and replace it if necessary ASM 262202.
If the fault continues:
. do a check of the PUSHBUTTON SWITCH-TEST (31WF) and replace it if necessary ASM 262202.
If the fault continues:
. do a check and repair the wiring ASM 262202 if necessary between the:
RELAY (39WF) connector A/X2 and RELAY (36WF) connector A/A1.
RELAY (36WF) connector A/A2 and RELAY (38WF) connector A/B1.
RELAY (38WF) connector A/B2 and GND.
RELAY (36WF) connector A/X2 and GND.
RELAY (37WF) connector A/B1 and RELAY (36WF) connector A/X1.
C/B (30WF) and RELAY (37WF) connector A/X1 and A/B2.
RELAY (37WF) connector A/X2 and GND.
RELAY (38WF) connector A/X2 and GND.
RELAY (33WF) connector A/D1 and RELAY (38WF) connector A/X1.
C/B (30WF) and RELAY (33WF) connector A/D2.
RELAY (38WF) connector A/C1 and RELAY (37WF) connector A/C1.
C/B (30WF) and RELAY (38WF) connector A/C2.

3 If the P5 light does not illuminate:

do a check fo the EXITING GROUND TEST RELAY (39WF) and replace it if necessary ASM 262202.

If the fault continues:

. do a check and repair the wiring ASM 262202 if necessary between the:
1186VC connector A and RELAY (39WF) connector A/A1.
RELAY (39WF) connector A/X1 and A/A2 and RELAY (43WF) connector A/A2.
RELAY (39WF) connector A/A1 and RELAY (35WF) connector A/X1.
4 If the P3 light does not illuminate:

do a check and repair the wiring ASM 262202 if necessary between the:
Connector 1186VC pin C and RELAY (38WF) connector A/A1.
RELAY (38WF) connector A/A2 and RELAY (39WF) connector A/A1.

5 If the P4 light does not illuminate:

do a check and repair the wiring ASM 262202 if necessary between the:
1186VC connector B and RELAY (36WF) connector A/B2.
RELAY (36WF) connector A/B1 and RELAY (38WF) connector A/A1.
RELAY (35WF) connector A/A2 and RELAY (36WF) A/B2.

. Push the RESET (32WF) pushbutton switch.

6 If the P2, P3, P4 and P5 does not illuminate correctly for 3 seconds, the RELAY (37WF) does not operate correctly.

replace the RELAY (37WF).

If the fault continues:
. do a check of the RELAY (34WF) and replace it if necessary ASM 262202.
If the fault continues:
. do a check of the RELAY (35WF) and replace it if necessary ASM 262202.
If the fault continues:
. do a check and repair the wiring ASM 262202 if necessary between the:
RELAY (34WF) connector A/X2 and RELAY (39WF) connector A/X2.
RELAY (34WF) connector A/X1 and RELAY (43WF) connector A/A2.
RELAY (34WF) connector A/A1 and RELAY (35WF) connector A/A1.
RELAY (34WF) connector A/A2 and INDICATOR LIGHT CONTROL BOX (1LP) connector A pin 24.

Subtask 26-22-00-810-066-A

C. If the ON legend in the APU/AUTO/EXTING TEST p/bsw does not come on during the test:

do the operational test of the annunciator light test system AMM 33-14-00-710-001.

(1) If the fault continues:

do a check of the PUSHBUTTON SWITCH-TEST (31WF) and replace it if necessary ASM 262202.

(2) If the fault continues:

do a check of the PUSHBUTTON SWITCH-RESET (32WF) and replace it if necessary ASM 262202.

(3) If the fault continues:

do a check of the RELAY-TEST (33WF) and replace it if necessary ASM 262202.

(4) If the fault continues:

do a check and repair the wiring if necessary between the:
PBSW TEST (31WF) connector A/4 and RELAY (33WF) connector A/C2,
PBSW TEST (31WF) connector A/A1 and RELAY (33WF) connector A/X1 and A/A1,
RELAY (33WF) connector A/C1 and GND,
RELAY (33WF) connector A/X2 and GND,
RELAY (33WF) connector A/A2 and C/B (30WF) ASM 262202.

Subtask 26-22-00-810-071-A

D. With the Test-tool Box
(1) If the ON legend in the APU/AUTO/EXTING TEST p/bsw does not come on during the test:

do the operational test of the annunciator light test system AMM 33-14-00-710-001.

(a) If the fault continues:

do a check of the PUSHBUTTON SWITCH-TEST (31WF) and replace it if necessary ASM 262202.

(b) If the fault continues:

do a check of the PUSHBUTTON SWITCH-RESET (32WF) and replace it if necessary ASM 262202.

do a check of the RELAY-TEST (33WF) and replace it if necessary ASM 262202.

(d) If the fault continues:

do a check and repair the wiring if necessary between the:
PBSW TEST (31WF) connector A/4 and RELAY (33WF) connector A/C2,
PBSW TEST (31WF) connector A/A1 and RELAY (33WF) connector A/X1 and A/A1,
RELAY (33WF) connector A/C1 and GND,
RELAY (33WF) connector A/X2 and GND,
RELAY (33WF) connector A/A2 and C/B (30WF) ASM 262202.
RELAY (32WF) and RELAY (31WF) connector A/A3.

Subtask 26-22-00-710-058-A

E. Do the test as given in the Para. 3.A.

5. Close-up
Subtask 26-22-00-860-053-A

A. Put the aircraft back to its initial configuration.

[Rev.8 from Aug 2018] 2026.04.04 04:27:24 UTC