When one of the conditions that follow detected by the Slat Flap Control Unit (SFCU) 1 occurs:

• The differential position/velocity between the left skew sensor 3 and left skew sensor 4 is more than the thresholds
• The absolute position of the left skew sensor 3 or left skew sensor 4 at the retract position is more than the rig tolerance
• The position of the left skew sensor 3 or left skew sensor 4 is more than the range limit

• Left Flap Skew Sensor 3 (MT70)
• Left Flap Skew Sensor 4 (MT71)
• Slat Flap Control Unit (SFCU) 1 (A124)
• Associated Wiring

Advisory Wire/Service Bulletin: None

Forum Articles/Infoservice/Newsletter: None

Temporary reset procedure:

If the flaps are failing and needs to be moved in half speed with the fault active, there is a way to move them without touching the flap mechanical system:

1. Select the SFCU#1 CNTRL CB to OUT on the EMS CDU
2. Perform a slat flap reset on the EMS CDU
3. Clear the latched fault in the SFCU#2
4. Perform another slat flap reset on the EMS CDU
5. The flaps should move in half speed

NOTE: Before and during the flap motion make sure 1 person is outside close to the left flap actuator #3 and pull the Slat Flap Power #2 AC thermal breaker if a strange noise is noticed.

Monitoring of the left skew sensor #3 and #4 on CAIMS:

1. SYSTEM DIAG
2. 27-00 FLIGHT CONTROLS
3. SLAT/FLAP CONTROL UNIT #1
4. LRU TEST
5. SLAT/FLAP POSITION RAW DATA SFCU1
6. CONFIRM

NOTE 1: The raw position of the skew sensor #4 can be calculated like this: (SKEW 3 count) - (3 Minus 4 count)= SKEW 4 count.

NOTE 2: A negative value applied to a minus action would result in the addition of the two values.

NOTE 3: The value provided by the SFCU#2 can be different due to the mechanical adjustment of the flaps on the wings but must be close to the value provided by the SFCU#1.

Clear Fault:

Performing a SLAT FLAP RESET on the EMS CDU may clear this fault.

NOTE: Wait at least one minute after SFCU reset to allow self test to run.

Moving the SFCL to another detent may also clear this fault.

Performing the clear latched fault may also clear this fault.

Clear Slat/Flap Control Unit (SFCU) Latched Faults	AMM 27-51-05-910-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Removal of the Slat/Flap Control Unit (SFCU)	AMM 27-51-05-000-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Installation of the Slat/Flap Control Unit (SFCU)	AMM 27-51-05-400-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Rigging of the Flap System	AMM 27-52-00-820-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Removal of the Flap-System Torque Tubes	AMM 27-52-01-000-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Installation of the Flap-System Torque Tubes	AMM 27-52-01-400-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Removal of the Flap System Actuators	AMM 27-52-09-000-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Installation of the Flap-System Actuators	AMM 27-52-09-400-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Detailed Inspection of the Inner-Flap Panel Support-Fitting	AMM 27-52-21-220-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Detailed Inspection of the Middle-Flap Panel Support-Fittings	AMM 27-52-25-220-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Detailed Inspection of the Outer-Flap Panel Support-Fittings	AMM 27-52-29-220-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Removal of the Flap Skew Sensor	AMM 27-52-45-000-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Installation of the Flap Skew Sensor	AMM 27-52-45-400-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Access to System Diagnostics	AMM 45-45-00-970-804 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Wire Repair - Maintenance Practices - ALL	SPM 20-12-10-02 [ Global Express ]  [ G5000 ]  [ Global XRS ]

1. Cycle the flaps from 0 degree to 30 degrees then back to 0 degree.
   NOTE: If necessary use the temporary reset procedure provided in the Troubleshooting Tips. Make sure the flaps are fully retracted.
2. Perform the electrical rigging of the flaps in CAIMS on the SFCU 2.

   1. If system checks are good, do close out.
   2. If fault remains, continue with next step.

3. Swap SFCU 1 with SFCU 2.

   1. If system checks are good, replace SFCU 1 and do close out.
   2. If fault remains, continue with next step.

4. Select the flaps to 0 degree and confirm that the flap skew sensor 3 and 4 are not at less then 0 degree. Select the flaps to 30 degrees and make sure the skew sensor 3 is not at more then 8810 counts and the skew sensor 4 is not at more then 9549.

   1. If 2 skew sensors are within the range, continue with next step.
   2. If any of the 2 skew sensors exceed the minimum or maximum range, replace the faulty skew sensor.

      1. If system checks are good, do close out.
      2. If fault remains, continue with next step.

5. Perform wiring checks between skew sensors and SFCU 1.

   1. If wiring checks are not good, repair defective wiring as required and do close out.
   2. If wiring checks are good, continue with next step.

6. Perform a general visual inspection of the flap actuators, flap carriage assemblies, and flap tracks.

   1. If inspection procedure fix the fault, do close out.
   2. If fault remains, continue with next step.

7. Disconnect the torque tube from the left side of the PDU.
8. Access the CAIMS system diagnostic and release the left flap asymmetric brake from the SFCU 1 or 2.

   1. SYSTEM DIAG
   2. 27-00 FLIGHT CONTROLS
   3. SLAT/FLAP CONTROL UNIT 1(2)
   4. LRU TEST
   5. FLAP RIGGING - SFCU 1(2)
   6. Confirm
   7. Highlight "FLAP RIG ENABLE COMMAND" and Select
   8. Highlight "RELEASE L FLAP ABRAKE" and Select"

NOTE 1: Highlight "ENGAGE L FLAP ABRAKE and "select" when the check is done.

NOTE 2: If the power is not available on the A/C, 28 VDC can be apply on the Asymmetric brake. Do not apply 28 VDC to Abrake for more than one minute. Remove voltage for a minimum of five minutes before you apply 28 VDC again. If it is necessary to extend the brake release time, decrease the voltage to 12 VDC. If you do not obey these instructions, you can cause damage to Abrake.

9. Manually turn the flap drive line to move the left flap panels and make sure the left flap drive line turns freely (less than 50 lbf in (5.65 Nm).

WARNING: Make sure that no persons and equipment are near the flaps. The movement of the flaps can cause injury to persons and damage to the equipment.

CAUTION: Do not apply more than 50 lbf in (5.65 Nm) to the torque tube shaft. If you do this, you can cause damage to the over-travel stops.

10. Isolate high resistance to turn at each actuator if flap drive line resistance is greater than 50 lbf in (5.65 Nm).

    1. If system checks are good, do close out.
    2. If fault remains, continue with next step.

11. Replace affected actuator.
12. Do close out.