W DOC AIRBUS | TSM A320F

No Buzzer Function after Key Pad Operation

TASK 52-51-00-810-802-A
No Buzzer Function after Key Pad Operation

1. Possible Causes
  • KEYPAD [25MQ]
  • BUZZER [23MQ]
  • CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ]
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
AMM 52-51-00-710-003
Operational Test of the Emergency Access
ASM 525101
AMM 52-51-13-000-001
Removal of the Buzzer of the Cockpit-Door Locking System
AMM 52-51-13-400-001
Installation of the Buzzer of the Cockpit-Door Locking System
AMM 52-51-14-000-001
Removal of the Control Unit of the Cockpit-Door Locking System
AMM 52-51-14-400-001
Installation of the Control Unit of the Cockpit-Door Locking System
AMM 52-51-15-000-001
Removal of the Key Pad
AMM 52-51-15-400-001
Installation of the Keypad
3. Fault Confirmation
Subtask 52-51-00-710-051-A
A. Do the operational test of the emergency access AMM 52-51-00-710-003.
4. Fault Isolation
Subtask 52-51-00-810-056-B
A. If the buzzer at the cockpit ceiling panel 211HC does not come on:
  • Enter the emergency entry code and make sure that the green LED at the KEYPAD [25MQ] flashes.
   (1) If the green LED at the KEYPAD [25MQ] flashes:
  • Do a check of 28 VDC at the BUZZER [23MQ] .
     (a) If there is no 28 VDC:
  • Do a check for continuity between the BUZZER [23MQ] and the CB(1MQ) ASM 525101.
       1 If there is no continuity:
  • Do a check and repair the wiring between the BUZZER [23MQ] and the CB(1MQ) ASM 525101.
       2 If there is continuity:
  • Do a check for continuity between the CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ] connector A/C and the BUZZER [23MQ] ASM 525101.
         a If there is continuity:
         b If there is no continuity:
  • Do a check and repair the wiring between the BUZZER [23MQ] and the CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ] connector A/C ASM 525101.
     (b) If there is 28 VDC:
  • Do a check for continuity on the BUZZER [23MQ] .
       1 If there is no continuity:
       2 If there is continuity:
   (2) If the green LED at the KEYPAD [25MQ] does not flash:
  • Do a check of the voltage between the pins G and K of the CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ] .
     (a) If there is no voltage:
     (b) If there is voltage:
  • Do a check of the voltage between the KEYPAD [25MQ] connectors A/15 and A/8 ASM 525101.
       1 If there is no voltage:
  • Do a check and repair the wiring between:
    The KEYPAD [25MQ] connector A/15 and CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ] connector B/G ASM 525101.
    The KEYPAD [25MQ] connector A/8 and CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ] connector B/K ASM 525101.
       2 If there is voltage:
  • Do a check for continuity between the CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ] connector B/E and the KEYPAD [25MQ] connector A/9 ASM 525101.
  • Do a check for continuity between the CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ] connector B/F and the KEYPAD [25MQ] connector A/10 ASM 525101.
         a If there is no continuity:
  • Do a check and repair the wiring between the CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ] connector B/E and the KEYPAD [25MQ] A/9 ASM 525101.
  • Do a check and repair the wiring between the CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ] connector B/F and the KEYPAD [25MQ] A/10 ASM 525101.
         b If there is continuity:
     (c) If the fault continues:
  • Do a check for continuity between the CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ] connector B/A and the KEYPAD [25MQ] connector A/1 ASM 525101.
  • Do a check for continuity between the CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ] connector B/B and the KEYPAD [25MQ] connector A/2 ASM 525101.
  • Do a check for continuity between the CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ] connector B/C and the KEYPAD [25MQ] connector A/3 ASM 525101.
  • Do a check for continuity between the CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ] connector B/D and the KEYPAD [25MQ] connector A/4 ASM 525101.
       1 If there is no continuity:
  • Do a check and repair the wiring between the CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ] connector B/A and the KEYPAD [25MQ] connector A/1 ASM 525101.
  • Do a check and repair the wiring between the CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ] connector B/B and the KEYPAD [25MQ] connector A/2 ASM 525101.
  • Do a check and repair the wiring between the CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ] connector B/C and the KEYPAD [25MQ] connector A/3 ASM 525101.
  • Do a check and repair the wiring between the CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ] connector B/D and the KEYPAD [25MQ] connector A/4 ASM 525101.
       2 If there is continuity:
5. Close-up
Subtask 52-51-00-710-052-A
A. Do the test given in para. 3.
[Rev.8 from Aug 2018] 2026.04.04 04:34:55 UTC
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