Fault Message:

LEFT COWL AI VALVE CMD /L CAIV

Fault Code:

3615315BMC

Associated CAS:

L COWL A/ICE FAIL
(Caution)

L COWL A/ICE FAULT
(Advisory)

The Left Cowl Anti-Ice Valve position reported to the Bleed Management Controller (BMC) does not agree with the L COWL ANTI-ICE switch position or does not regulate the pressure properly. Inhibited during take-off and Landing.

• Left Engine Cowl Anti-Ice Valve (CAIV)
• Left Engine Cowl Anti-Ice Valve (CAIV) Switch
• Bleed Air Control Panel (AP8)
• Anti-Ice Left Cowl Switch (S9)
• Cowl Anti-Ice Relay (K1)
• Cowl Anti-Ice Relay (K2)
• Ice Detector 1 (E48)
• Ice Detector 2 (E49)
• Left Engine Cowl Anti-Ice Pressure Transducer
• Left Engine In-line Pressure Regulator Valve
• Bleed Management Controller (BMC) 1 (A69)
• Associated Wiring

Advisory Wire/Service Bulletin:

• AW700-36-0365 - Bleed management controller - Data Gathering to Reduce No Fault Found (NFF) rate

Forum Articles/Infoservice/Newsletter:

• Forum Article 2011-VOL 8 issue 23

NOTE: Make sure the BMC Questionnair is filled out and sent to Bombardier.

CAIV Position and Status Logic (used for synoptic page).

1. On the PMAT, access CAIMS -> SYSTEM DIAG -> ATA 36 -> Select BMC 1 -> LRU TEST -> L BMC Discrete & analog input data. On the Bleed Air Control panel, set the L CAIV switch to all three positions consecutively while observing the CAIMS BMC data page.
   

   1. If the switch position displayed on the data page does not match with the actual switch position, go to step 17.
   2. When compared with the right side data page (BMC 2), if the LH COWL AI Pressure displayed on the data page is not correct, go to step 19.
   3. If the Cowl A/Ice Valve position displayed on the data page does not match the actual position of the CAIV, continue with next step.
      NOTE: If engine is off, the CAIV has to be in the OPEN position, independent of switch position.

2. Check if fault code 3615315BMC was set on ground.

   1. If NO, go to step 6.
   2. If YES, continue with next step.

3. Ensure the engine has been shut down at least for 1 minute and the Cowl Anti-Ice Valve switch is selected OFF. Is the 'L COWL A/ICE FAULT' advisory CAS message still present?

   1. If NO, do close out.
   2. If YES, continue with next step.

4. Open the COWL doors and locate the CAIV. Check the CAIV V-Band clamps position.

   1. If the V-Band clamps are not installed 90 degrees off-set from each other, re-orientate the V-Band clamps so that they are oriented 90 degrees from each other and do close out.
   2. If the V-Band clamps are installed 90 degrees offset from each other, continue with next step.

5. Verify the valve butterfly position by observing the Output Shaft (OPS) position.

   1. If the OPS is retracted and the CAIV is displayed CLOSED on the Bleed Air/Anti-Ice synoptic page, go to step 7.
   2. If the OPS is fully extended, replace the CAIV and do close out.

6. Check the Pressure Transducer vent hole for installation clamp obstruction. Obstructing the Pressure Transducer vent hole will result in false pressure measurements and the display of CAI error messages.

   1. If the Pressure Transducer vent hole is covered by the installation clamps, rectify as required and do close out.
   2. If the Pressure Transducer vent hole is not obstructed, continue with next step.

7. Swap CAIVs.

   1. If system checks are good, replace defective CAIV and do close out.
   2. If fault remains, continue with next step.

8. Disconnect the left CAIV connector P720. On the Bleed Air control Panel, set the L CAIV switch to "ON". Make sure there is no voltage at P720-1.

   1. If there is no voltage, go to step 11.
   2. If there is voltage, continue with next step.

9. Perform a wiring check between the CAIV and the Bleed Air Control Panel.

   1. If wiring checks are not good, repair defective wiring as required and do close out.
   2. If wiring checks are good, continue with next step.

10. Replace the L CAIV switch.

    1. If system checks are good, do close out.
    2. If fault remains, continue with next step.

11. On the Bleed Air control Panel, set the L CAIV switch to "OFF". Make sure there is 28 VDC at P720-1.

    1. If there is 28 VDC, go to step 13.
    2. If there is no voltage, continue with next step.

12. Perform a wiring check between the CAIV and the Bleed Air Control Panel.

    1. If wiring checks are not good, repair defective wiring as required and do close out.
    2. If wiring checks are good, go to step 19.

13. Disconnect CAIV connector P719 and P720. Disconnect BMC 1 connector A69P1. Perform a continuity check as follows:

    From	To	Expected Result	Result
    P719-3	Ground	Open
    P719-4	Ground	Continuity
    P719-5	Ground	Continuity
    P720-2	Ground	Continuity
    P720-3	Ground	Continuity

    1. If there is continuity, repair defective wiring as required and do close out.
    2. If there is no continuity, continue with next step.

14. Perform a continuity check as follows:

    From	To	Result
    P719-3	A69P1-13

    1. If there is no continuity, repair defective wiring as required and do close out.
    2. If there is continuity, continue with next step.

15. Disconnect Bleed Air Control Panel connectors AP8P3 and AP8P4. Perform a continuity check as follows:

    From	To	Result
    AP8P3-32	Ground
    AP8P4-32	Ground

    1. If there is no continuity, go to step 18.
    2. If there is continuity on AP8P4-32, go to step 17.
    3. If there is continuity on AP8P3-32, continue with next step.

16. Disconnect the Left Ice detector connector A48P1. Perform a continuity check as follows:

    From	To	Result
    AP8P3-32	Ground

    1. If there is continuity, repair defective wiring as required and do close out.
    2. If there is no continuity, replace the Left Ice Detector and continue with next step.

17. Disconnect the Right Ice detector connector A49P1. Perform a continuity check as follows:

    From	To	Result
    AP8P4-32	Ground

    1. If there is continuity, repair defective wiring as required and do close out.
    2. If there is no continuity, replace the Right Ice Detector and continue with next step.

18. Disconnect the Left Ice detector connector A48P1 and the Right Ice detector connector A49P1. Perform a continuity check as follows:

    From	To	Result
    AP8P3-32	E48P1-6
    AP8P4-32	E49P1-6

    1. If there is no continuity, repair defective wiring as required and do close out.
    2. If there is continuity, continue with next step.

19. Perform a 28 VDC voltage check on AP8P3-31. Is 28 VDC present?

    1. If YES, go to step 21.
    2. If NO, continue with next step.

20. Make sure the L COWL A/ICE VLV circuit breaker is set to "IN" and perform a wiring check between Bleed Air Control Panel and SPDA 2.

    1. If wiring checks are not good, repair defective wiring as required and do close out.
    2. If wiring checks are good, continue with next step.

21. Perform a continuity check directly on the Bleed Air Control Panel as follows: L CAIV Switch position "ON":

    From	To	Expected Result	Result
    AP8J3-31	AP8J3-33	Open
    AP8J3-27	Panel Ground	Continuity
    AP8J3-28	Panel Ground	Open

    L CAIV Switch position "OFF":

    From	To	Expected Result	Result
    AP8J3-31	AP8J3-33	Continuity
    AP8J3-27	Panel Ground	Open
    AP8J3-28	Panel Ground	Continuity

    L CAIV Switch position "AUTO":

    From	To	Expected Result	Result
    AP8J3-31	AP8J3-33	Continuity
    AP8J3-31	Panel Ground	Continuity
    AP8J3-27	Panel Ground	Open
    AP8J3-28	Panel Ground	Open

    1. If the results are as per the table above, go to step 23.
    2. If the results are not as per the table above, continue with next step.

22. Test the internal wiring of the panel, the L CAIV switch and the two relays (K1 and K2).

    1. If wiring checks are not good, repair defective wiring as required and do close out.
    2. If wiring checks are good, continue with next step.

23. If defects are suspected with the K1 or K2 relays and perform a continuity check as follows: For K1:

    From	To	Expected result	Result
    X1	X2	Continuity
    A2	A3	Continuity
    C1	C2	Open
    D2	D3	Continuity

    For K2:

    From	To	Expected result	Result
    X1	X2	Continuity
    B2	B3	Continuity
    A1	A2	Open
    D2	D3	Continuity

    1. If the test results are as expected, please note that it is possible a contact is "tack welded" in the de-energized position. If it is the case, only a test performed with power can reveal the defect.
    2. If results are not as in the tables above, continue with next step.

24. Replace defective relay(s).

    1. If system checks are good, do close out.
    2. If fault remains, continue with next step.

25. Swap the left Cowl Anti-Ice Pressure transducer and right Cowl Anti-Ice Pressure transducer.

    1. If system checks are good, replace left Cowl Anti-Ice Pressure transducer and do close out.
    2. If fault remains, continue with next step.

26. Disconnect CAI Pressure transducer connector P718. Using a voltmeter, make sure there is 28 V at P718-1.

    1. If there is 28 VDC, go to step 28.
    2. If there is no voltage, check to make sure L BMC SENSORS circuit breaker is "IN" and continue with next step.

27. Perform wiring checks between the Pressure sensor and SPDA 4.

    1. If wiring checks are not good, repair defective wiring as required and do close out.
    2. If wiring checks are good, continue with next step.

28. Disconnect BMC 1 connector A69P1. Perform a continuity check as follows:

    From	To	Expected Result	Result
    P718-4	Ground	Continuity
    P718-5	Ground	Continuity
    P718-2	Ground	Open
    P718-3	Ground	Open

    1. If there is continuity, repair defective wiring as required and do close out.
    2. If there is no continuity, continue with next step.

29. Perform a continuity check as follows:

    From	To	Result
    P718-2	A69P1-1
    P718-3	A69P1-6

    1. If there is no continuity, repair defective wiring as required and do close out.
    2. If there is continuity, continue with next step.

30. Perform troubleshooting of 3615425BMC.

    1. If system checks are good, do close out.
    2. If fault remains, continue with next step.

31. Swap BMC 1 with BMC 2. Is the fault still present?

    1. If NO, replace BMC 1 and do close out.
    2. If YES, continue with next step.

32. Replace the in-line pressure regulator valve.
33. Do close out.