05/06/21
Message Overview:
Message Description:
Aircraft ARINC system fault to left engine.
[MCID 1505]
ARINC system.
A fault related to the aircraft ARINC data system was sensed.
- Loss of ARINC data reception or validity in input of FADEC
- Loss or invalidity of LP or HP bleed source coming from IOCs
- Loss or invalidity of ADC Mach Number in input of the FADEC
Possible Causes:
- Air Data Computer (ADC) (A1)
- Engine Bleed PBAs - Anti-Ice/Air Cond (PL19)
- Integrated Air System Controllers (IASC1) (A55)
- Integrated Air System Controllers (IASC2) (A56)
- Input/Output Concentrator (IOC) (A4-IOC)
- Junction Box 1 (JB1)
- Wing Cross-Bleed Valve (MPE10)
- Data Concentrator Unit (DCU) (A14)
- Associated Wiring
Troubleshooting Tips:
Advisory Wire/Service Bulletin:
- AW300-36-0008 - Wing Anti-ice Leak CAS message.
Forum Articles/Infoservice/Newsletter: None
- If both L & R ENG THRUST FAULT are posted at the same time, first suspect the Wing Anti-Ice (WAI) PBA or the Stall Protection Computer (SPC), which are common to both engines.
- If ENG THRUST FAULT comes along with faults related to airspeed, altitude, stab, trim or spoiler, or following a change of Air Data Source selection on the Reversion Select Panel, the ADC is most likely the root cause.
- If when cycling a Bleed PBA, the CAS message comes and goes, the fault is likely a discrepancy between the actual bleed status and the bleed command, possibly due to an ARINC failure.
- Experience has shown that not turning the WAI OFF after a "WING ANTI-ICE LEAK" CAS message could lead to an "ENG THRUST FAULT" CAS message. Refer to the AW listed above for more details.
- When Batteries are "ON" and engines are not running, if WAI is "ON" while the rotary switch is on "NORM", the L & R ENG THRUST FAULT CAS message will display.
- Check for the following MDC messages displayed with the fault:
- - X-channel bus 1A (MCID 0905),
- - X-channel bus 1B (MCID 0906),
- - X-channel discrete 1A (MCID 0933),
- - X-channel discrete 1B (MCID 0934).
If any of the above MCID codes are posted, correct the cross channel faults first.
Quick Links:
| Removal of the Integrated Air System (IAS) Controller | AMM 21-31-01-000-801 |
| Installation of the Integrated Air System (IAS) Controller | AMM 21-31-01-400-801 |
| Operational Test of the Integrated Air System (IAS) Controller | AMM 21-31-01-710-801 |
| Functional Test of the Stall Protection System | AMM 27-32-00-720-801 |
| Removal of the Stall Protection Computer | AMM 27-32-01-000-801 |
| Installation of the Stall Protection Computer | AMM 27-32-01-400-801 |
| Removal of the Input/Output Concentrator Unit (IOC) | AMM 31-45-05-000-801 |
| Installation of the Input/Output Concentrator Unit (IOC) | AMM 31-45-05-400-801 |
| Operational Test of the Input/Output Concentrator Unit (IOC) | AMM 31-45-05-710-801 |
| Removal of the Air Data Computer | AMM 34-13-01-000-801 |
| Installation of the Air Data Computer | AMM 34-13-01-400-801 |
| Functional Test of the Air Data Computer | AMM 34-13-01-720-801 |
| Removal of the Switch/Light | SPM 20-11-05-000-801 |
| Installation of the Switch/Light | SPM 20-11-05-400-801 |
| Wiring - Maintenance Practices - ALL | SPM 20-12-00-02 |
| Wire Repair - Maintenance Practices - ALL | SPM 20-12-10-02 |
| Electrical Connectors - Maintenance Practice - ALL | SPM 20-20-00-02 |
Troubleshooting Recommendations:
- Are any of the following CAS messages also displayed?
- If YES, start troubleshooting with those CAS message, as L/R ENG THRUST FAULT is likely a consequence of the other CAS message root cause.
- If not, continue with next step.
- Check CAS messages displayed on the cockpit and go into the MDC to check if any of the following fault codes are present:
- Interrogate the MDC as follows:
- On the cursor control panel, ensure the toggle switch is to the right and select Anti-Ice, ECS and Fuel buttons simultaneously. Press ENTER. The MDC main menu should now be displayed on Display Unit #3.
- Using the joystick, select Current Faults (if the fault is active) or Aircraft History to research stored faults. From Aircraft History you can then select 'Fault History' and locate the fault. Going into advanced diagnostics will provide an Equation ID for the fault identified.
- Select the MDC fault or equation from the drop down below to provide additional information to assist in troubleshooting.
- If one or more of these B3 codes is present in the MDC, and/or if any CAS message related to TRIM, SPOILERS, FLAPS or STALL is displayed, continue with next step.
- If none of these B3 codes is present in the MDC and no CAS message related to TRIM, SPOILERS, FLAPS or STALL is displayed, go to step 5.
- Interrogate the MDC as follows:
- Check the wires and connections between
- ADC 1 A1P1 pins 20 & 21 and the IAPS A4P1 pins 17 & 18.
- IAPS A4P1 pins 73 & 74 and FADEC Channel B A43J1/W2P2 (P801) pins 91 & 92.
- IAPS A4P1 pins 73 & 74 and W1P1/J803 pins 58 & 59.
- W1P1/J803 pins 58 & 59 and FADEC Channel A A41J1/W1P2 pins 91 & 92.
- IAPS A4P101 pins 73 & 74 and FADEC Channel B A43J1/W2P2 (P801) pins 87 & 88.
- IAPS A4P101 pins 73 & 74 and W1P1/J803 pins 69 & 70.
- W1P1/J803 pins 69 & 70 and FADEC Channel A A41J1/W1P2 pins 87 & 88.
- If damage is found, repair or replace the damaged part per SPM. Do close out.
- If no damage is found, continue with next step.
- Interchange ADC 1 and ADC 2. Check if 'L ENG THRUST FAULT' is still displayed.
- If 'L ENG THRUST FAULT' is still present, remove and replace left IOC. Do close out.
- If 'R ENG THRUST FAULT' is present, remove and replace ADC 2 (after interchange). Do close out.
- Is the R ENG THRUST FAULT CAS message displayed at the same time as L ENG THRUST FAULT?
- If YES, continue with next step.
- If not, go to step 11.
- Check if Wing Cross-Bleed Valve (MPE10) is stuck OPEN.
- If YES, replace Wing Cross-Bleed Valve (MPE10).
- If NO, continue with next step.
- Set Wing Source Rotary switch on NORM and cycle WAI PBA.
- If the CAS message comes and goes when cycling the WAI PBA, continue with next step.
- If cycling the WAI PBA has no effect on the CAS message, go to step 11.
- Go into the MDC to check if SPC output ARINC label 271 bits 17 and 18 to FADEC ("WAI selected OFF A" & "WAI selected OFF B" (1=OFF, 0=ON)) follow the WAI PBA position.
- Interrogate the MDC as follows:
- On the cursor control panel, ensure the toggle switch is to the right and select Anti-Ice, ECS and Fuel buttons simultaneously. Press ENTER. The MDC main menu should now be displayed on Display Unit #3.
- Using the joystick, select LRU INDEX/OPERATIONS, then STALL COMPUTER (27-35) and look at Label 271 bits value.
- Interrogate the MDC as follows:
- Set Wing Source Rotary switch on NORM and cycle WAI PBA.
- If the Label 271 bits 17 & 18 follow the WAI PBA position, go to step 11.
- If the Label 271 bits 17 & 18 do not follow the WAI PBA position, continue with next step.
- Check wiring at SPC inputs A178AP1 and A178BP1 as follows:
- At SPC A178AP1 pin 20, make sure ground is available while Wing Anti-Ice is deselected (OFF).
- At SPC A178AP1 pin 20, make sure ground is NOT available while Wing Anti-Ice is selected (ON).
- At SPC A178BP1 pin 20, make sure ground is available while Wing Anti-Ice is deselected (OFF).
- At SPC A178BP1 pin 20, make sure ground is NOT available while Wing Anti-Ice is selected (ON).
- If wiring check failed, replace WAI selector switch. Do close out.
- If wiring check is good, replace SPC per AMM. Do close out.
- Cycle L BLEED PBA.
- If the CAS message disappears or reappears depending on the PBA position, continue with next step.
- If the CAS message remains even while cycling the PBA, go to step 16.
- Go into the MDC to check if L BLEED status given by IASC 1 follows PBA position while cycling the PBA.
- Interrogate the MDC as follows:
- On the cursor control panel, ensure the toggle switch is to the right and select Anti-Ice, ECS and Fuel buttons simultaneously. Press ENTER. The MDC main menu should now be displayed on Display Unit #3.
- Using the joystick, select LRU TESTING then IASC 1A. Choose TEST and press ENTER. Select AIR COND PANEL DISCRETE STATUS. Then select AIR COND/ENGINE PANEL STATUS.
- Interrogate the MDC as follows:
- Cycle the L BLEED STATUS PBA and check if L BLEED status (LEFT BLEED OFF: YES or NO) follows the PBA position. Note result and continue with next step.
- Go back to MDC main menu and check if L BLEED status delivered by IASC 2 follows PBA position while cycling the PBA.
- Interrogate the MDC as follows:
- Return to the MDC main menu displayed on Display Unit #3.
- Using the joystick, select LRU TESTING then IASC 2A. Choose TEST and press ENTER. Select AIR COND PANEL DISCRETE STATUS. Then select AIR COND/ENGINE PANEL STATUS.
- Interrogate the MDC as follows:
- Cycle the L BLEED STATUS PBA and check if L BLEED status (LEFT BLEED OFF: YES or NO) follows the PBA position.
- If L BLEED status does not follow the PBA position at steps 13 and 15, replace L BLEED PBA. Do close out.
- If L BLEED status follows the PBA position only at step 13 and not at step 15, replace the IASC 2.
- If L BLEED status follows the PBA position only at step 15 and not at step 13, replace the IASC 1.
- If L BLEED status follows the PBA position at steps 13 and 15, continue with next step.
- Refer to the Honeywell LMM (Subtask 72-00-00-810-322-A01).