Failure of the Engine 1 Air Intake Anti-Ice Valve in the Open Position

TASK 30-21-00-810-801-A
Failure of the Engine 1 Air Intake Anti-Ice Valve in the Open Position

1. Possible Causes

VALVE-ENG AIR INTAKE ANTI ICE [4000DN]
P/BSW-ANTI ICE/ENG 1 [2DN1]
wiring between pin A/10 of the engine 1 air intake anti-ice valve and the ground terminal
wiring between pin A/9 of the engine 1 air intake anti-ice valve and the circuit breaker (1DN1)
C/B [1DN1]
defective muscle pressure tubes and hoses

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
AMM 30-21-00-710-002	Operational Test of the Engine Air Intake Ice Protection (with the Engines in operation)
ASM 302101
AMM 30-21-49-210-001	Visual Inspection of the Anti-Ice System Tubes, Ducts, and Hoses
AMM 30-21-51-000-040	Removal of the Engine Air-Intake Anti-Ice Valve
AMM 30-21-51-000-041	Removal of the Engine Air-Intake Anti-ice Valve
AMM 30-21-51-400-041	Installation of the Engine Air-Intake Anti-Ice Valve
AMM 30-21-51-400-042	Installation of the Engine Air-Intake Anti-ice Valve
AMM 36-11-00-720-007	Functional Test of the Sense Lines Connected to the Bleed Pressure-Regulator Valve with the Bleed Test Set P/N 98D36003000000

3. Fault Confirmation
Subtask 30-21-00-710-052-A ** ON A/C NOT FOR ALL

A. Test
Do the operational test of the engine air intake ice protection AMM 30-21-00-710-002.

4. Fault Isolation
Subtask 30-21-00-810-050-B ** ON A/C NOT FOR ALL

A. If the test confirms the fault:

Do a check of the status of the ANTI ICE/ENG/1 circuit breaker (1DN1).

(1) If the circuit breaker is closed:

Do a check for 28VDC at pin A/9 of the engine 1 air intake anti-ice valve (4000DN):

(a) If there is 28VDC:

Replace the VALVE-ENG AIR INTAKE ANTI ICE [4000DN] AMM 30-21-51-000-040 and AMM 30-21-51-400-041.

(b) If there is no 28VDC:

Do a check for 28VDC at pin A/D2 of the ANTI ICE/ENG 1 pushbutton switch (2DN1).

1 If there is 28VDC:

Replace the P/BSW-ANTI ICE/ENG 1 [2DN1] .

2 If there is no 28VDC:

Do a check for a ground signal at pin A/10 of the engine 1 air intake anti-ice valve:

a If there is no ground signal:

Repair the wiring between pin A/10 of the engine 1 air intake anti-ice valve and the ground terminal ASM 302101.

b If there is a ground signal:

Do a check of the wiring between pin A/9 of the engine 1 air intake anti-ice valve and the circuit breaker (1DN1).

c If there is no continuity:

Repair the above wiring.

d If there is continuity:

Replace the C/B [1DN1] .

(2) If the circuit breaker is open:

Do the circuit breaker tripped procedure (Ref. TSM TASK 24-00-00-810-803).

(a) If the fault continues:

Replace the C/B [1DN1] .

(b) If the fault continues:

Do the functional test of the sense lines AMM 36-11-00-720-007.

1 If there are leaks:

Repair the defective muscle pressure tubes and hoses AMM 30-21-49-210-001.

2 If there is no leak:

Replace the VALVE-ENG AIR INTAKE ANTI ICE [4000DN] .

Subtask 30-21-00-810-050-E ** ON A/C NOT FOR ALL