B3-006660 - NO SIGNAL/OUT OF RANGE [DIFF PRESS SNSR1]

02/02/21

Message Overview:

Message Name:

NO SIGNAL / OUT OF RANGE

Message Code:

B3-006660

Associated CAS:

Reporting LRU:	DIFF PRESS SNSR 1
System Description:	21-51-00
Schematic Diagram:	21-61-00
Wiring Diagram:	21-61-21

Messge Description:

The DIFFERENTIAL PRESSURE SENSOR 1 is detected failed. No signal is received or the signal is out of range. Check the sensor or the wiring to the sensor and the IASC # 1.

Possible Causes:

Differential Pressure Sensor 1 (MT23)
Integrated Air System Controller (IASC #1) (A55)
Junction Box 1 (JB1)
Junction Box 3 (JB3)
Associated Wiring

Troubleshooting Tips:

Advisory Wire/Service Bulletin: None

Forum Articles/Infoservice/Newsletter: None

Quick Links:

Removal of the Integrated Air System (IASC) Controller	AMM 21-31-01-000-801
Installation of the Integrated Air System (IASC) Controller	AMM 21-31-01-400-801
Removal of the Differential Pressure Sensor	AMM 21-51-03-000-801
Installation of the Differential Pressure Sensor	AMM 21-51-03-400-801
Removal of the Junction Boxes	AMM 24-63-01-000-802
Installation of the Junction Boxes	AMM 24-63-01-400-802
Operational Test of the Bleed Air System	AMM 36-11-00-710-801
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:

Reset the L WING / BLD LK circuit breakers CB1-E10.
1. If system checks are good, do close out.
2. If fault remains, continue with next step.
Swap the Differential Pressure Sensor 1 with the Differential Pressure Sensor 2.
1. If system checks are good, do close out.
2. If fault remains, continue with next step.
Do wiring check between the Differential Pressure Sensor 1 (MT23) and the IASC 1. Repair as required.
1. If system checks are good, do close out.
2. If fault remains, continue with next step.
Swap the IASC 1 with the IASC 2.
1. If system checks are good, do close out.
2. If fault remains, continue with next step.
Do wiring check between the Differential Pressure Sensor 1 (MT23) and the JB1. Repair as required.
1. If system checks are good, do close out.
2. If fault remains, continue with next step.
Do wiring check of JB1. Replace JB1 as required.
1. If system checks are good, do close out.
2. If fault remains, continue with next step.
Do wiring check between JB1 and JB3. Repair as required.
1. If system checks are good, do close out.
2. If fault remains, continue with next step.
Do wiring check of JB3. Replace JB3 as required.
1. If system checks are good, do close out.
2. If fault remains, continue with next step.
Do wiring check of JB3 and the Circuit Breaker CB1-E10. Repair as required.
Do close out.