04/13/21
Message Overview:
Message Description:
Left engine surge bleed valve C fault 1A
[MCID 0414]
SBV C 1A.
A fault in the SBV C harness between the SBV C and the ECU A was sensed.
Possible Causes:
- Wiring Harness (W5)
- Wiring Harness (W4)
- Surge Bleed Valve (SBV) C
- Full Authority Digital Engine Control Unit (FADEC) Electronic Control Unit A (ECU) (A41)
Troubleshooting Tips:
Advisory Wire/Service Bulletin: None
Forum Articles/Infoservice/Newsletter: None
- If the L or R ENG MINOR FAULT CAS message is shown with this fault, this is a Short Term dispatch (STD) fault and is subject to correction outlined in the Honeywell LEMM SUBTASK 5-10-00-200-003.
- If a L or R FADEC FAIL CAS message is shown, this is a No Dispatch (ND) fault and is subject to correction outlined in the Honeywell LEMM SUBTASK 5-10-00-200-003.
- Check for the following MDC messages displayed with the fault: X-channel bus 1A (MCID 0905), X-channel bus 1B (MCID 0906), X-channel discrete 1A (MCID 0933), X-channel discrete 1B (MCID 0934). If any of the above MCID codes are posted, correct the cross channel faults first.
- Issues with the N1 shutoff (Broken Shaft Connector), or bleed surge valves, contact Honeywell FSR and find out about status of Dash 12 W5 harness. Ref Honeywell S/B AS907-76-9011. Most likely tied to connector pin friction or loose connector.
Quick Links:
| Removal of the Trim-Surge Bleed Valves | AMM 75-31-06-000-801 |
| Installation of the Trim-Surge Bleed Valves | AMM 75-31-06-400-801 |
| Removal of the Engine Electronic Control Unit (ECU) | AMM 76-10-05-000-801 |
| Installation of the Engine Electronic Control Unit (ECU) | AMM 76-10-05-400-801 |
| Wiring - Maintenance Practices - ALL | SPM 20-12-00-02 |
| Wire Repair - Maintenance Practices - ALL | SPM 20-12-10-02 |
| Electrical Connectors - Maintenance Practice - ALL | SPM 20-20-00-02 |
Troubleshooting Recommendations:
- MCID 0414 fault only is present, troubleshoot using the following steps for aircraft and engine fault isolation with reference to the Light Engine Maintenance Manual TASK 72-00-00-700-058.
- Reset and reboot the ECU to recheck the MDC MCID for the posted fault.
- Remove the connector on the ECU 1A, W4P13 and inspect for burned or pushed back pins/sockets, particularly pins 55 and 50, inspect for damage, then check the following segments per the table, repair wiring if required per the wiring manual standard practices.
- On pins W4P13 pins 55 and 50, document the resistance value down through the coil of the Solenoid A of Surge Bleed Valve C. Resistance should be 10 to 80Ω, IAW Honeywell LMM.
- Remove the W3 harness on the bottom of the engine W4P16. Consider ringing out the SBV C, particularly on pin 6 and 7 of W5J9.
- Check the connection on the SBV B by examining W5J7.
From To Value W4P13 Pin 55 W4P13 Pin 50 10 to 80 Ω W5J9 Pin 6 W5J9 Pin 7 10 to 80 Ω W5P7 Pin 1 W5P7 Pin 2 10 to 80 Ω - If the wiring is good and the valve solenoid resistance is out of limits, replace SBV C Surge Bleed Valve IAW AMM TASK 75-31-05-000-801, TASK 75-31-05-400-801.
- If the wiring and SBV check good, consider swapping the A and B ECUs for the left engine, remove and replace IAW AMM TASK 76-10-05-000-801, TASK 76-10-05-400-801.



