Fault Message:

L BVSB 8 CH B WRG/BVSB RNG MA

Fault Code:

7327121LBR

Associated CAS:

None

The fault message is set when:

• The resistance in solenoid 8 (channel B) of the Bleed Valve Solenoid Control Block (BVSB) is not within limits
• There is an open or short circuit in the interface wiring

The BVSB circuits are checked during power-up and continuously monitored by the Full-Authority Digital Engine-Controller (FADEC).

• Bleed Valve Solenoid Control Block (BVSB)
• Left Engine Electronic Controller (EEC)
• Associated Wiring

Advisory Wire/Service Bulletin: None

Forum Articles/Infoservice/Newsletter: None

1. Open the following circuit breakers:

System	Circuit Breaker Name	Bus Name
ENGINE	L FADEC CH A	BATT
ENGINE	L FADEC CH B	BATT
ENGINE	L ENG IGN 1	BATT
ENGINE	L ENG IGN 2	BATT
ENGINE	L ENG FUEL HPSOV	BATT
ENGINE	L ENG START A	BATT
ENGINE	L ENG START B	BATT
ENGINE	L T/R CTL VALVE	BATT
ENGINE	L T/R LOWER LOCK	BATT
ENGINE	L T/R UPPER LOCK	BATT

2. Perform a deactivation of the thrust reverser and open the cowls.
3. Remove the applicable bypass-duct access panel and the applicable compressor fairing.
4. Check if the fault message is stored.

   1. If the fault message is stored, the fault could be intermittent.
   2. If the fault message is not stored, continue with next step.

5. Disconnect the connector J1032 from the core lane B disconnect P1032 on bypass duct.
6. Perform a resistance check of the BVSB as follows:
   On A/C Post SB 75-101096:

   From	To	Resistance Value	Result
   P1032-1	P1032-6	70-90 ohms at 68 °F (20 °C) ±1.70 ohms per 9 °F (5 °C)
   P1032-1	Ground	>40 megohm

   On A/C Post SB 75-101161:

From	To	Resistance Value	Result
P1032-1	P1032-6	80-100 ohms at 68 °F (20 °C) ±1.70 ohms per 9 °F (5 °C)
P1032-1	Ground	>40 megohm

1. If the resistance values of the BVSB are not as specified, replace the BVSB and go to step 19.
2. If the resistance values of the BVSB are as specified, continue with next step.

7. Connect the connector J1032.
8. Close the following circuit breakers:

System Name	Circuit Breaker Name	Bus Name
ENGINE	L FADEC CH A	BATT
ENGINE	L FADEC CH B	BATT

9. Connect the electrical power to the aircraft.
10. Check if the fault message still exists.

    1. If fault message does not exist, go to step 19.
    2. If fault message still exists, remove the electrical power from the aircraft and continue with next step.

11. Open the following circuit breakers:

System Name	Circuit Breaker Name	Bus Name
ENGINE	L FADEC CH A	BATT
ENGINE	L FADEC CH B	BATT

CAUTION: DO NOT DO ELECTRICAL CHECKS INTO THE ENGINE ELECTRONIC CONTROLLER (EEC). IF YOU DO NOT OBEY THIS INSTRUCTION, DAMAGE TO THE EEC CAN OCCUR.

12. Perform wiring checks between the EEC connector P1047, bypass duct connector J1032 and the BVSB connector P1008.

    1. If wiring checks are not good, repair defective wiring as required and go to step 19.
    2. If wiring checks are good, continue with next step.

13. Close the following circuit breakers:

System Name	Circuit Breaker Name	Bus Name
ENGINE	L FADEC CH A	BATT
ENGINE	L FADEC CH B	BATT

14. Connect the electrical power to the aircraft.
15. Make sure that L (R) FADEC FAIL (caution) does not show on the EICAS display.

    1. If If L (R) FADEC FAIL (caution) shows on the EICAS display, troubleshoot them first and continue with next step.
    2. If If L (R) FADEC FAIL (caution) does not show on the EICAS display, continue with next step.

16. Remove the electrical power from the aircraft.
17. Check if the error message shows again.

    1. If the error message does not show again, go to step 19.
    2. If the error message shows again, continue with next step.

18. Replace Left EEC.
19. Close the cowls and activate thrust reverser.
20. Do close out.