Fly-by-Wire faults – Tips and resetting methods

Effectivity: Global 7500 aircraft 

ATA: 27-04 

By: Daniel Genois (Technical Services) 

In the Fly-by-Wire (FBW) system, it can sometimes be difficult to understand how faults are detected and what approach should be taken to clear them. 

A document containing pertinent information has been created to help maintainers with FBW system fault detection. This document also provides fault resetting methods (including AW700-27-0873 explanations and resetting method), troubleshooting tips and available OMS data, which can be used to improve fault isolation efficiency. 

The document is called "FBW Faults - tips and resetting methods" and is accessible in all FBW system SmartFix Plus (SFP) OMS faults under the “Troubleshooting Tips” section. The document also contains the following: 

1. Initiated Built in Test (IBIT) explanations 

2. Power up Built in Test (PBIT) 

3. Actuation Flight Control Built in Test (ABIT) 

4. REU Random Access Memory (RAM) Faults (SBIT) 

5. Continuous Built in Test (CBIT)  

6. FBW System latched faults 

7. REU faults vs. AFCU faults 

8. AW700-27-0873 explanations and resetting method 

9. Data available in the OMS 

   a. OMS Faults / MSG Data Tab 

   b. LRU Maintenance data pages 

   c. NVM download 

Before troubleshooting the FBW system, Bombardier strongly recommends that operators familiarize themselves with the "FBW Faults - tips and resetting methods" document. 

If you have any questions, please contact Technical Services or your local Field Service Representative (FSR).