Loss of the WHC 1

TASK 30-42-00-810-845-A
Loss of the WHC 1

1. Possible Causes

WHC-1 [2DG1]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
TSM TASK 30-42-00-810-801-A	Loss of the Left Windshield Temperature Sensor
AMM 30-42-00-710-001	Operational Test of the Windshield Anti-Icing and Defogging
ASM 304201
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)
Sensor Resistance Versus Temperature

3. Fault Confirmation
Subtask 30-42-00-710-122-A

A. Test
(1) Do the operational test of the windshield anti-icing and defogging AMM 30-42-00-710-001.

4. Fault Isolation
Subtask 30-42-00-810-106-A

A. If the test gives the maintenance message WHC1 2DG1:

Replace the WHC-1 [2DG1] , AMM 30-42-34-000-001 and AMM 30-42-34-400-001.

Subtask 30-42-00-810-107-A

B. If the test gives the maintenance message L WSHLD SENSOR (3DG1)/WHC (2DG1):
(1) Do a check of the L Windshield Temperature Information (Ref. TSM TASK 30-42-00-810-801).
(a) Verify if the resistance of the temperature sensor connected to the L windshield (3DG1) is out of the tolerance ASM 304201 and

Sensor Resistance Versus Temperature

For example, for OAT=20°C, the sensor value must be between 592 Ohms and 608 Ohms. If the sensor is out of tolerance, refer to (Ref. TSM TASK 30-42-00-810-801) to isolate the suspected sensor and to connect a serviceable sensor to the WHC.

5. Close-up
Subtask 30-42-00-710-123-A

A. Do the operational test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:29:44 UTC