07/06/21
Message Overview:
Message Name:
APU INLET PRESSURE OUT OF RANGE
| Message Code: | 496OBS001 |
| Effectivity: | All |
| System: | Airborne Auxiliary Power Unit (APU) |
| System Description: | 49-60-00 |
| Schematic Diagram: | 49-61-00 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Wiring Diagram: | 49-12-01 [ Global Express ] [ G5000 ] [ Global XRS ] 49-61-01 [ Global Express ] [ G5000 ] [ Global XRS ] |
Message Description:
The Full-Authority Digital Engine-Controller (FADEC) received incorrect Inlet Pressure Sensor inputs because of the conditions that follow:
- Inlet Pressure Sensor high side conditioning voltage in the FADEC is out of range high (this shows a possible open in the Inlet Pressure Sensor or the Engine Branched Wiring-Harness)
- Inlet Pressure Sensor high side conditioning voltage in the FADEC is out of range low and the signal read by the FADEC is out of range low (this shows a possible short to ground in the Inlet Pressure Sensor high side signal or the Engine Branched Wiring-Harness)
Possible Causes:
- Inlet Pressure Sensor (P2) (MT1)
- Full-Authority Digital Engine-Controller (FADEC) (A108)
- Associated Wiring
Troubleshooting Tips:
Advisory Wire/Service Bulletin: None
Forum Articles/Infoservice/Newsletter: None
Quick Links:
| APU Safety Precautions | AMM 49-00-00-910-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Removal of the Engine Branched Wiring-Harness | AMM 49-12-01-000-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Installation of the Engine Branched Wiring-Harness | AMM 49-12-01-400-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Removal of the Full-Authority Digital Engine-Controller (FADEC) | AMM 49-61-01-000-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Installation of the Full-Authority Digital Engine-Controller (FADEC) | AMM 49-61-01-400-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Removal of the Inlet Pressure Sensor | AMM 49-61-13-000-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Installation of the Inlet Pressure Sensor | AMM 49-61-13-400-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Wire Repair - Maintenance Practices - ALL | SPM 20-12-10-02 [ Global Express ] [ G5000 ] [ Global XRS ] |
Troubleshooting Recommendations:
- Examine the engine branched wiring-harness for bare wiring, kinks, worn areas and other damage (Refer WM 49-12).
- If there is bare wiring, kinks, worn areas or other damage, replace engine branched wiring-harness and do close out.
- If there is no damage, continue with next step.
- Examine the inlet pressure sensor (MT1) receptacle for contamination and damage.
- If there is contamination or damage, go to step 7.
- If there is no contamination or damage, continue with next step.
- Perform a resistance check as follows:
From To Expected Result Result MT1-A MT1-B 1000-4000 Ohms - If the resistance value is not as specified, go to step 7.
- If the resistance value is as specified, continue with next step.
- Perform a resistance check as follows:
From To Expected Result Result MT1-C MT1-D 500-2000 Ohms - If the resistance value is not as specified, go to step 7.
- If the resistance value is as specified, continue with next step.
- Perform wiring checks between APU (P802) and inlet pressure sensor (MT1P1).
- If the wiring checks are not good, replace the engine branched wiring-harness and do close out.
- If the wiring checks are good, continue with next step.
- Perform wiring checks between AC wiring harness (J802) and FADEC (A108AP1).
- If the wiring checks are not good, repair the defective wiring as required and do close out.
- If the wiring checks are good, replace FADEC (A108) and do close out.
- Replace the Inlet Pressure Sensor (MT1).
- Do close out.