06/30/21
Message Overview:
Message Name:
CBW FAILED IN OPEN POSITION
| Message Code: | 301OBS002 |
| Effectivity: | All |
| System: | Wing Cross Bleed Valve |
| System Description: | 36-11-00 |
| Schematic Diagram: | 36-11-00 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Wiring Diagram: | 30-11-03 [ Global Express ] [ G5000 ] [ Global XRS ] |
Message Description:
The Wing Cross Bleed Valve (or Wing Anti-Ice (WAI) Isolation Valve) failed in the open position.
Possible Causes:
- Wing Cross Bleed Valve (CBW) (L33)
- Secondary Power Distribution Assembly (SPDA) 4 (A16)
- Relay (K12)
- Junction Box (JB3)
- Associated Wiring
Troubleshooting Tips:
Advisory Wire/Service Bulletin: None
Forum Articles/Infoservice/Newsletter: None
Quick Links:
| Removal of the Junction Box JB3 | AMM 24-00-01-000-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Installation of the Junction Box JB3 | AMM 24-00-01-400-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Removal of the Secondary-Power Distribution Assemblies |
AMM 24-62-01-000-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Installation of the Secondary-Power Distribution Assemblies |
AMM 24-62-01-400-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Removal of the Wing Cross-Bleed Valve | AMM 30-11-09-000-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Installation of the Wing Cross-Bleed Valve | AMM 30-11-09-400-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Wire Repair - Maintenance Practices - ALL | SPM 20-12-10-02 [ Global Express ] [ G5000 ] [ Global XRS ] |
Troubleshooting Recommendations:
- On the Bleed Air Control Panel, set the WING XBLEED switch to the FROM L (FROM R) position.
- Measure for 28 VDC at CBW L33P1-3.
- If there is no 28 VDC, go to step 4.
- If there is 28 VDC, continue with next step.
- Replace CBW.
- If system checks are good, do close out.
- If fault remains, continue with next step.
- Perform wiring checks between SPDA 4, JB3, CBW and GS390.
- If wiring checks are not good, repair defective wiring as required and do close out.
- If wiring checks are good, continue with next step.
NOTE: Remove all interface components for short circuit test.
- Swap SPDA 4 with SPDA 3.
- If system checks are good, replace SPDA 4 and do close out.
- If fault remains, continue with next step.
- Replace K12/JB3.
- Do close out.