07/29/19
Message Overview:
Fault Message:
SCU INVALID
Fault Code:
3143112DAU
Associated CAS:
| Reporting LRU: | Data Acquisition Unit (DAU) 2 |
| System Description: | 31-40-00 |
| Schematic Diagram: | 31-42-00 [ Global Express ] [ G5000 ] [ Global XRS ] 32-51-00 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Wiring Diagram: | 31-42-02 [ Global Express ] [ G5000 ] [ Global XRS ] 32-51-01 [ Global Express ] [ G5000 ] [ Global XRS ] |
Fault Description:
The Data Acquisition Unit (DAU) 2 reports the Line Replaceable Unit (LRU) label 270 is transmitted with an incorrect Source Destination Identifier (SDI) or an invalid Sign Status Matrix (SSM).
Possible Causes:
- Steering Control Unit (SCU) (A36)
- Data Acquisition Unit (DAU) 2 (A18)
- Associated Wiring
Troubleshooting Tips:
Advisory Wire/Service Bulletin: None
Forum Articles/Infoservice/Newsletter: None
Quick Links:
| Connect Electrical Power to the Aircraft | AMM 24-00-00-861-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Remove the Electrical Power from the Aircraft | AMM 24-00-00-861-802 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Opening of Non-Thermal Circuit Breakers | AMM 24-00-00-863-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Closing of Non-Thermal Circuit Breakers | AMM 24-00-00-863-802 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Electrical/Electronic Safety Precautions | AMM 24-00-00-910-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Removal of the Data Acquisition Units (DAU) | AMM 31-42-01-000-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Installation of the Data Acquisition Units (DAU) | AMM 31-42-01-400-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Functional Test of the Nosewheel-Steering Control System |
AMM 32-51-00-720-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Removal of the Steering Control Unit | AMM 32-51-01-000-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Installation of the Steering Control Unit | AMM 32-51-01-400-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Safety Precautions - Maintenance Practices - ALL | SPM 20-00-01-02 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Wire Repair - Maintenance Practices - ALL | SPM 20-12-10-02 [ Global Express ] [ G5000 ] [ Global XRS ] |
Troubleshooting Recommendations:
- In the flight compartment, on the LDG GEAR control panel, set the NOSE STEER switch to ARMED.
- Remove SCU to get access to the connector A36P1. Check if there is 26 to 30 VDC between the pins of the connectors that follows:
From To Expected Result Result A36P1-8 A36P1-3 26 to 30 VDC A36P1-9 A36P1-5 26 to 30 VDC - If there is no 26 to 30 VDC, perform the power check and do close out.
- If there is 26 to 30 VDC, continue with the next step.
- In the flight compartment, on the LDG GEAR control panel, set the NOSE STEER switch to OFF. Remove DAU 2 to get access to the connector A18CP1 and perform a continuity check as follows:
From To Result A18CP1-D3 A36P1-2 A18CP1-E3 A36P1-6 A18CP1-SH A36P1-SH - If there is no continuity, repair or replace defective wiring as required and do close out.
- If there is continuity, continue with the next step.
- Perform a continuity check as follows:
From To Result A18CP1-D3 Ground A18CP1-E3 Ground - If there is continuity, repair or replace defective wiring as required and do close out.
- If there is no continuity, continue with the next step.
- Swap DAU 2 with DAU 4. Is the fault still present?
- If NO, replace DAU 2 and do close out.
- If YES, continue with next step.
- Replace the SCU.
- Do close out.