Message Name:

N2 OVERSPEED ID 1B

Message Code:

B3-303650

Associated CAS:

L ENGINE MINOR FAULT
(Advisory)

Left engine N2 overspeed identification fault 1B.

[MCID 0602]
N2 Overspeed ID 1B.
Detection of a fault in the harness that defines the N2 overspeed identification or the ECU B. The ECU B cannot support full system operation.

• Aircraft Connector (P801)
• Full Authority Digital Engine Control (FADEC) Electronic Control Unit B (ECU) (A43)

Advisory Wire/Service Bulletin: None

Forum Articles/Infoservice/Newsletter: None

1. If the 'L' or R ENGINE MINOR FAULT' advisory 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.
2. 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.
3. 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.

1. MCID 0602 fault only is present, troubleshoot using the following steps for aircraft and engine fault isolation with reference to the Light Engine Maintenance Manual TASK 72-00-00-810-076.