Failure of the GLC 2 Status Indication

TASK 24-22-00-810-826-A
Failure of the GLC 2 Status Indication

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
ASM 242203
AMM 24-22-34-000-001	Removal of the GCU-1(2)
AMM 24-22-34-400-001	Installation of the GCU-1(2)
AMM 24-22-55-000-001	Removal of the Contactors
AMM 24-22-55-400-002	Installation of the Contactors
AMM 24-41-00-740-002	Operational Check of the GAPCU via the CFDS

3. Fault Confirmation
Subtask 24-22-00-740-063-A ** ON A/C NOT FOR ALL

A. Test
(1) Do the BITE test of the GAPCU AMM 24-41-00-740-002.
(a) If the BITE test gives the message TEST FAILED:

(b) If the BITE test gives the message TEST PASSED:

4. Fault Isolation
Subtask 24-22-00-810-089-A ** ON A/C NOT FOR ALL

A. If the BITE test gives the message TEST FAILED:

(1) If the maintenance message GCU2 (1XU2) comes into view:

Subtask 24-22-00-810-078-A ** ON A/C NOT FOR ALL

B. If the BITE test gives the message TEST PASSED:

do a check of the contact for correct operation of the GLC 2 (9XU2) between pins B/18 and B/20 ASM 242203.

(1) If the contact does not operate correctly:

(2) If the contact operates correctly:

do a check of the wiring of the GLC 2 sence circuit ASM 242203 for an open circuit between:
. pin 2 of the ELEC/GCU2 circuit breaker (2XU2) and pin B/18 of the GLC 2 (9XU1)
. pin B/20 of the GLC 2 and pin A/30 of the diode module 2420VD
. pin A/15 of the diode module 2420VD and pin A/6A of the GCU 2.

(a) If the wiring is not correct:

(b) If the wiring is correct:

Subtask 24-22-00-740-064-A ** ON A/C NOT FOR ALL

C. When you replace a component or repair the wiring:

do the subsequent flight before you do the check of the Class 3 Faults of the GAPCU from the CFDS to make sure that the system operates correctly.
If the test continues to give the fault message, continue the trouble shooting procedure.

[Rev.8 from Aug 2018] 2026.04.04 04:26:38 UTC