W DOC AIRBUS | TSM A320F

Loss of Power Supply of the WHC 2


TASK 30-42-00-810-830-A
Loss of Power Supply of the WHC 2


1. Possible Causes
  • WHC-2 [2DG2]
  • wiring between the WHC 2 (2DG2) pin B/R and the ground terminal
  • wiring between the WHC 2 pin B/S and the circuit breaker (5DG2)
  • C/B-ANTI ICE/WHC/2 [5DG2]
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
ASM 304202
AMM 30-42-34-000-001
Removal of the Window Heat Computer (WHC)
AMM 30-42-34-400-001
Installation of the Window Heat Computer (WHC)
AMM 31-32-00-869-002
Procedure for the Class 3 Fault Reading
3. Fault Confirmation
Subtask 30-42-00-740-052-A
A. Test
   (1) On the CFDS MENU page, get access to the AVIONICS STATUS page AMM 31-32-00-869-002.
4. Fault Isolation
Subtask 30-42-00-865-063-A
A. Table of the circuit breakers used in this procedure:
PANELDESIGNATIONFINLOCATION
** ON A/C ALL
122VUANTI ICE/WHC/25DG2W13
Subtask 30-42-00-810-079-A
B. If the test gives the maintenance message NO WHC 2 DATA:
  • do a check of the status of the circuit breaker (5DG2).
   (1) If the circuit breaker is closed:
  • do a check for 28VDC at pin B/S of the WHC 2 (2DG2) ASM 304202.
     (a) If there is 28VDC:
     (b) If there is no 28VDC:
  • do a check for a ground signal at pin B/R of the WHC 2 (2DG2).
       1 If there is no ground signal:
  • repair the wiring between the WHC 2 (2DG2) pin B/R and the ground terminal.
       2 If there is a ground signal:
  • do a check of the wiring between the WHC 2 pin B/S and the circuit breaker (5DG2).
         a If there is no continuity:
  • repair the above wiring.
         b If there is continuity:
  • Replace the circuit breaker (5DG2).
   (2) If the circuit breaker is open:
     (a) If the fault continues:
  • Replace the C/B-ANTI ICE/WHC/2 [5DG2] .
     (b) If the fault continues:
  • Replace the WHC-2 [2DG2] .
Subtask 30-42-00-740-053-A
C. Do the BITE test given in Para. 3.
[Rev.8 from Aug 2018] 2026.04.04 04:29:43 UTC