Loss of the WHC 2 Output Bus by the CFDIU

TASK 31-32-00-810-898-A
Loss of the WHC 2 Output Bus by the CFDIU

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
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
ASM 313206
AMM 31-32-34-000-001	Removal of the CFDIU
AMM 31-32-34-400-001	Installation of the CFDIU

3. Fault Confirmation
Subtask 31-32-00-865-145-A

A. Make sure that this(these) circuit breaker(s) is(are) closed:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
123VU	ANTI ICE/R/WHSLD	1DG2	AF03

Subtask 31-32-00-740-242-A

B. Test
On the CFDS MENU page, get access to the AVIONICS STATUS page AMM 31-32-00-869-002.

4. Fault Isolation
Subtask 31-32-00-810-148-A

A. If the test gives the maintenance message NO WHC2 DATA:

(1) If the fault continues:

(2) If the fault continues:

do a check and repair the wiring from the CFDIU (1TW) to the WHC 2 (2DG2) from pins AB/8F, 8G to pins B/M, N ASM 313206.

Subtask 31-32-00-740-243-A

B. Do the test given in Para. 3.B.

[Rev.8 from Aug 2018] 2026.04.04 04:29:56 UTC