Fault Message:

RIGHT FDBK LVDT/WRG

Fault Code:

3250011DWY

Associated CAS:

NOSE STEER FAIL
(Caution)

Nose Wheel Steering Control Unit (SCU) has detected a fault with the Right Position Feedback Linear Variable Differential Transformer (LVDT) (Right Steering Actuator).

• Right Steering Actuator Position Feedback Linear Variable Differential Transformer (LVDT) (MT16)
• Steering Control Unit (SCU) (A36)
• Associated Wiring

Advisory Wire/Service Bulletin:

• AW700-32-0280 - Nose Wheel Steering Troubleshooting SCU GW415-8100-3

Forum Articles/Infoservice/Newsletter: None

NOTE: The Actuator position feedback LVDTs position can be monitored into CAIMs under the Steering Control Unit (SCU) and Nose Wheel Steering Discrete inputs for SCU-3.

1. Make sure the Nose Steer switch on the Landing Gear control Panel is set to "ARM". Make sure the SCU is powered.

   1. If fault indication is gone, do close out.
   2. If fault remains, continue with next step.

2. Re-seat the SCU.

   1. If fault indication is gone, do close out.
   2. If fault remains, continue with next step.

3. Perform the Right steering actuator/feedback position LVDT rigging in CAIMS via the System Diagnostics, ATA 32, Steering Control Unit, LRU Test page. Make a selection of the rigging for the proper unit P/N. Follow instructions on the PMAT.

   1. If fault indication is gone, do close out.
   2. If fault remains, continue with next step.

4. Perform wiring check between the SCU connector (A36P1) and the RH Steering Actuator LVDT (MT16) as follows:

   From	To	Result
   A36P1-44	A36P1-45
   A36P1-46	A36P1-47
   A36P1-46	A36P1-48
   A36P1-47	A36P1-48

   1. If wiring checks are good, go to step 6.
   2. If wiring checks are not good, repair defective wiring as required and continue with next step.
      NOTE: While wiring checks are being accomplished have a second person 'shake down' wiring along the top side of the actuators. Inspect wiring on Actuators carefully for extreme bends and kinks or breaks.

5. Disconnect the right Feedback LVDT and perform a wiring check as follows:

   From	To	Result
   A36P1-44	MT16-1
   A36P1-45	MT16-2
   A36P1-48	MT16-13
   A36P1-47	MT16-12
   A36P1-46	MT16-11

   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 the Rigging of the Nose wheel Steering Control System.

   1. If fault indication is gone, do close out.
   2. If fault remains, continue with next step.

7. Replace the right Steering Actuator.

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

8. Replace SCU.
9. Do close out.