Failure of the BSV Valve on Engine 1

TASK 73-10-00-810-833-A
Failure of the BSV Valve on Engine 1

1. Possible Causes

burner staging valve
harness J8
HMU-1 [4000KC1]
ECU [4000KS]
burner staging valve (BSV)

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 72-41-00-290-001	Borescope Inspection of the Combustion Chamber Liners, Dome Areas, HPT Nozzle Vanes and Shrouds (as far as visible through two opposite ports)
AMM 72-51-00-290-002	Borescope Inspection of the High-Pressure Turbine-Nozzle Assembly
AMM 72-51-00-290-004	Borescope Inspection of High-Pressure Turbine Nozzle Assembly
AMM 73-11-70-000-001	Removal of the Burner Selection Valve (BSV)
AMM 73-11-70-000-002	Removal of the Burner Selection Valve (BSV) for SAC Engines
AMM 73-11-70-400-001	Installation of the Burner Selection Valve (BSV)
AMM 73-11-70-400-002	Installation of the Burner Selection Valve (BSV) for SAC Engines
AMM 73-21-10-000-001	Removal of the Hydromechanical Unit (HMU)
AMM 73-21-10-000-002	Removal of the Hydromechanical Unit (HMU)
AMM 73-21-10-400-001	Installation of the Hydromechanical Unit (HMU)
AMM 73-21-10-400-002	Installation of the Hydromechanical Unit (HMU)
AMM 73-21-50-000-007	Removal of J8 Harness
AMM 73-21-50-000-041	Removal of the HJ8 Harness for SAC Engines
AMM 73-21-50-400-007	Installation of the J8 Harness
AMM 73-21-50-400-041	Installation of the HJ8 Harness for SAC Engines
AMM 73-21-60-000-001	Removal of the Electronic Control Unit (ECU)
AMM 73-21-60-400-001	Installation of the Electronic Control Unit (ECU)
ASM 732518
AMM 73-29-00-710-040	Operational Test of the FADEC on the ground (with Engine Motoring)

3. Fault Confirmation
Subtask 73-10-00-710-112-A ** ON A/C NOT FOR ALL

A. Do the operational test of the FADEC 1B on the ground (with engine motoring) AMM 73-29-00-710-040.

4. Fault Isolation
Subtask 73-10-00-810-090-B ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message BSV (VLV CLSD), HMU:

NOTE: If the ENG 1 CTL VALVE FAULT ECAM warning comes into view simultaneously with this fault message, you must do a borescope inspection of the combustion chambers AMM 72-41-00-290-001 and the high-pressure turbine-nozzle assembly AMM 72-51-00-290-004 before the next flight.

disconnect the connector J8 from the ECU (4000KS) and do a check of the ECU cable resistance between:
. pins 6 and 7 (26 to 36 ohms) ASM 732518.

(1) If the resistance values are in the specified limits:
(a) If the burner staging valve has been deleted:

No more action is necessary.

(b) If the burner staging valve is installed:

Replace the burner staging valve AMM 73-11-70-000-002 and AMM 73-11-70-400-002.

(2) If the resistance values are out of the specified limits:

disconnect the harness J8 from the HMU and do a check of the HMU resistance between:
. pins 6 and 7 (26 to 36 ohms).

(a) If the resistance values are in the specified limits:

replace the defective harness J8 AMM 73-21-50-000-041 and AMM 73-21-50-400-041.

(b) If the resistance values are out of the specified limits:

replace the HMU-1 [4000KC1] AMM 73-21-10-000-002 and AMM 73-21-10-400-002.

(3) If the fault continues after the replacement of the BSV and the harness J8, or if the burner staging valve has been deleted, and if the resistance checks are correct, the cause of the fault can be the hydraulic pressure control:

replace the HMU-1 [4000KC1] AMM 73-21-10-000-002 and AMM 73-21-10-400-002.

(4) If the fault continues:

replace the ECU [4000KS] AMM 73-21-60-000-001 and AMM 73-21-60-400-001.

Subtask 73-10-00-810-091-B ** ON A/C NOT FOR ALL

B. If the test gives the maintenance message BSV (VLV OPEN), HMU:

disconnect the connector J8 from the ECU (4000KS) and do a check of the ECU cable resistance between:
. pins 6 and 7 (26 to 36 ohms) ASM 732518.

(1) If the resistance values are in the specified limits:
(a) If the burner staging valve has been deleted:

No more action is necessary.

(b) If the burner staging valve is installed:

Replace the burner staging valve AMM 73-11-70-000-002 and AMM 73-11-70-400-002.

(2) If the resistance values are out of the specified limits:

disconnect the harness J8 from the HMU and do a check of the HMU resistance between:
. pins 6 and 7 (26 to 36 ohms).

(a) If the resistance values are in the specified limits:

replace the defective harness J8 AMM 73-21-50-000-041 and AMM 73-21-50-400-041.

(b) If the resistance values are out of the specified limits:

replace the HMU-1 [4000KC1] AMM 73-21-10-000-002 and AMM 73-21-10-400-002.

replace the HMU-1 [4000KC1] AMM 73-21-10-000-002 and AMM 73-21-10-400-002.

(4) If the fault continues:

replace the ECU [4000KS] AMM 73-21-60-000-001 and AMM 73-21-60-400-001.

Subtask 73-10-00-810-090-C ** ON A/C NOT FOR ALL

C. If the test gives the maintenance message BSV (VLV CLSD), HMU:

disconnect the connector J8 from the ECU (4000KS) and do a check of the ECU cable resistance between:
. pins 6 and 7 (26 to 36 ohms) ASM 732518.

(1) If the resistance values are in the specified limits:

replace the burner staging valve (BSV) AMM 73-11-70-000-001 and AMM 73-11-70-400-001.

(2) If the resistance values are out of the specified limits:

disconnect the harness J8 from the HMU and do a check of the HMU resistance between:
. pins 6 and 7 (26 to 36 ohms).

(a) If the resistance values are in the specified limits:

replace the defective harness J8 AMM 73-21-50-000-007 and AMM 73-21-50-400-007.

(b) If the resistance values are out of the specified limits:

replace the [4000KC1] AMM 73-21-10-000-001 and AMM 73-21-10-400-001.

(3) If the fault continues after the replacement of the BSV and the harness J8 and if the resistance checks are correct, the cause of the fault can be the hydraulic pressure control:

replace the [4000KC1] AMM 73-21-10-000-001 and AMM 73-21-10-400-001.

(4) If the fault continues:

replace the ECU [4000KS] AMM 73-21-60-000-001 and AMM 73-21-60-400-001.

Subtask 73-10-00-810-091-C ** ON A/C NOT FOR ALL

D. If the test gives the maintenance message BSV (VLV OPEN), HMU:

disconnect the connector J8 from the ECU (4000KS) and do a check of the ECU cable resistance between:
. pins 6 and 7 (26 to 36 ohms) ASM 732518.

(1) If the resistance values are in the specified limits:

replace the burner staging valve (BSV) AMM 73-11-70-000-001 and AMM 73-11-70-400-001.

(2) If the resistance values are out of the specified limits:

disconnect the harness J8 from the HMU and do a check of the HMU resistance between:
. pins 6 and 7 (26 to 36 ohms).

(a) If the resistance values are in the specified limits:

replace the defective harness J8 AMM 73-21-50-000-007 and AMM 73-21-50-400-007.

(b) If the resistance values are out of the specified limits:

replace the [4000KC1] AMM 73-21-10-000-001 and AMM 73-21-10-400-001.

(3) If the fault continues after the replacement of the BSV and the harness J8 and if the resistance checks are correct, the cause of the fault can be the hydraulic pressure control:

replace the [4000KC1] AMM 73-21-10-000-001 and AMM 73-21-10-400-001.

(4) If the fault continues:

replace the ECU [4000KS] AMM 73-21-60-000-001 and AMM 73-21-60-400-001.

Subtask 73-10-00-710-113-A ** ON A/C NOT FOR ALL

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

[Rev.8 from Aug 2018] 2026.04.04 04:35:15 UTC