12/07/23
Message Overview:
Message Name:
CH B FAULT
(Service Message)
Message Code:
B3-006459
Associated CAS:
| Reporting LRU: | CKPT T SEL PNL |
| System Description: | 21-61-00 |
| Schematic Diagram: | SMM 21-61-00-101 - Temperature Control and Indication |
| Wiring Diagram: | 21-61-00 - Cabin/Cockpit Temperature Control - ALL |
Message Description:
The Channel B of the COCKPIT TEMPERATURE SELECTOR located on the bleed/air conditioning panel is detected failed.
Possible Causes:
- Cockpit Temperature Selector (CKSEL) (R02)
- Air Cond/Bleed Control Panel (PL17)
- Integrated Air System Controller (IASC2) (A56)
- Associated Wiring
Troubleshooting Tips:
Advisory Wire/Service Bulletin: None
Forum Articles/Infoservice/Newsletter: None
Fault Confirmation Procedure:
{Term Definitions}
- IAS2A-61 XX 353 10 EXCT XXXX-XXXX XXTX-XXXX XXXX-XXXX 353A: 22; COCKPIT TEMP SELECTOR B
- IAS1A-56 XX 353 00 EXCT XXXX-XXXX XXTX-XXXX XXXX-XXXX 353A: 22; COCKPIT TEMP SELECTOR A
Quick Links:
| Standard Aircraft Configuration for Maintenance | AMM 12-00-00-867-803 |
| 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 |
| Electrical/Electronic Safety Precautions | AMM 24-00-00-910-801 |
| Electrostatic-Discharge Safety Precautions | AMM 24-00-00-910-802 |
| Connect Electrical Power to the Aircraft | AMM 24-00-00-861-801 |
| Remove the Electrical Power from the Aircraft | AMM 24-00-00-861-802 |
| Removal of the Bleed-Air Control Panel | AMM 36-11-57-000-801 |
| Installation of the Bleed-Air Control Panel | AMM 36-11-57-400-801 |
| General | SPM20-20-00-02-01 |
| Connector Integrity After a Disconnect and Re-Connection | SPM20-20-00-02-06 |
Troubleshooting Recommendations:
- Check resistance of cockpit temp selector at connector PL17J2 between pin 45 and 47. Expected result 9.5 kΩ. If the resistance value is other than 9.5 kΩ, replace the potentiometer R2.
- Check resistance of cockpit temp selector at connector PL17J2 between pin 46 and 47 while rotating the knob. Expected result, linear variant from 0 to 9.5 kΩ. If the resistance is not linear up to 9.5 kΩ replace the potentiometer R2.
- Do a continuity check between connector PL17P2 pin 45 to connector A56P2 pin 78.
- Do a continuity check between connector PL17P2 pin 46 to connector A56P2 pin 70.
- Do a continuity check between connector PL17P2 pin 47 to connector A56P2 pin 71.
- If all the above is good, swap IASC 1 with IASC 2.
- If fault follows, replace faulty IASC.