Loss of the Bleed Transferred-Pressure Transducer of the Engine 1

TASK 36-11-00-810-817-A
Loss of the Bleed Transferred-Pressure Transducer of the Engine 1

1. Possible Causes

wiring between pin A/2 of the bleed transferred-pressure transducer (7HA1) and the ground terminal
wiring between pin A/1 of the bleed transferred-pressure transducer (7HA1) and the circuit breaker (2HA1)
XDCR-BLEED TRANSFER PRESS, ENG 1 [7HA1]
wiring from the bleed transferred-pressure transducer (7HA1) to the BMC1 (1HA1)
C/B-AIR BLEED/ENG 1/MONG [2HA1]
BMC-1 [1HA1]

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 361101
AMM 36-11-15-000-001	Removal of the Bleed Transferred Pressure-Transducer
AMM 36-11-15-400-001	Installation of the Bleed Transferred Pressure-Transducer

3. Fault Confirmation
Subtask 36-11-00-710-066-A ** ON A/C NOT FOR ALL

A. Not applicable.

4. Fault Isolation
Subtask 36-11-00-865-051-A ** ON A/C NOT FOR ALL

A. Table of the circuit breakers used in this procedure:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	AIR BLEED/ENG 1/MONG	2HA1	D11

Subtask 36-11-00-810-058-A ** ON A/C NOT FOR ALL

B. If the fault symptom is identified by the maintenance message TRANSF-PRESS XDCR 7HA1:

Do a check of the status of the circuit breaker (2HA1).

(1) If the circuit breaker is closed:

Do a check for 28VDC at pin A/1 of the bleed transferred-pressure transducer (7HA1) ASM 361101.

(a) If there is no 28VDC:

Do a check for ground at pin A/2 of the bleed transferred-pressure transducer (7HA1).

1 If there is no ground:

Repair the wiring between pin A/2 of the bleed transferred-pressure transducer (7HA1) and the ground terminal.

2 If there is ground:

Do a check of the wiring between pin A/1 of the bleed transferred-pressure transducer (7HA1) and the circuit breaker (2HA1).

a If there is no continuity:

Repair the above wiring.

b If there is continuity:

Replace the circuit breaker (2HA1).

3 If the fault continues:

Make sure that there is a 0 psig output signal (0.9VDC) on the BMC1 (1HA1) connector between pins AA/14B and AA/15B.

a If there is no 0.9VDC:

Replace the XDCR-BLEED TRANSFER PRESS, ENG 1 [7HA1] AMM 36-11-15-000-001 and AMM 36-11-15-400-001.

4 If the fault continues:

Do a check and repair the wiring from the bleed transferred-pressure transducer (7HA1) to the BMC1 (1HA1), pins A/3 and A/4 to pins AA/15B and AA/14B.

(b) If there is 28VDC:

Replace the XDCR-BLEED TRANSFER PRESS, ENG 1 [7HA1] .

(2) If the circuit breaker is open:

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

(a) If the fault continues:

Replace the C/B-AIR BLEED/ENG 1/MONG [2HA1] .

(b) If the circuit breaker stays closed and the fault continues:

Replace the BMC-1 [1HA1] .

Subtask 36-11-00-810-058-B ** ON A/C NOT FOR ALL

B. If the fault symptom is identified by the Class 3 maintenance message:
36-11-15
DRIFT TRANSF-PRESS XDCR 7HA1

Do a check of the status of the circuit breaker (2HA1).