background
x
loader
Troubleshooting
arrow By ATA By Message Color By Observed Faults by MDCBy Tips

Select color for CAS message that you wish to troubleshoot

(WARNING)
RED MESSAGE (CAUTION)
AMBER MESSAGE (ADVISORY)
CYAN MESSAGE (STATUS)
WHITE MESSAGE Require immediate crew attention. These messages are accompanied by flashing master warning, triple chime attenson with or without voice message or dedicated tone. Require immediate crew awareness and future crew action may be required in the form of alternate system selection or performance limitation. These message are accompanied by flashing master caution and a single chime. Indicate safe or normal system operation which require crew awareness, over and above the dark cockpit philosophy. Indicate minor failures or reduction in systems capability, which require no crew action.

This page includes :

For AOG assistance contact:

CRC Montreal (YUL)
Quick Links

03/16/21

Message Overview:

Message Name:

OB ARINC PRESS DISAGREE

Message Code:

B3-224430

Associated CAS:

BRAKE FAULT
(Advisory)

Reporting LRU: OB PRESS SWITCH
System Description: 32-43-00
Schematic Diagram: 32-43-00
Wiring Diagram: 32-43-00

Message Description:

The BCU detects a discrepancy between the right hydraulic system pressure and the outboard brake pressure switch (S98).

Possible Causes:

  • Brake Pressure Switch (RH) (S98)
  • Brake Control Unit (BCU) (A67)
  • Associated Wiring

Troubleshooting Tips:

Advisory Wire/Service Bulletin: None

Forum Articles/Infoservice/Newsletter: None

Quick Links:

Removal of the Brake Control Unit AMM 32-43-01-000-801
Installation of the Brake Control Unit AMM 32-43-01-400-801
Removal of the Brake Pressure Switch AMM 32-43-45-000-801
Installation of the Brake Pressure Switch AMM 32-43-45-400-801
Data Download from the Maintenance Diagnostic Computer (MDC) AMM 45-45-01-970-802
Standard Practices - Replace Wiring SPM 20-12-00-02
Standard Practices - Electrical Wiring-Continuity Test - Adjustment/Test SPM 20-12-01-05
Standard Practices - Wire Repair SPM 20-12-10-02

Troubleshooting Recommendations:

  1. Reset RCBP-C15 (INBD BRAKES).

    1. If the 'BRAKE FAULT' CAS message did not reappeared, do close out.
    2. If the 'BRAKE FAULT' CAS message still posted, continue with next step.

  2. Disconnect the outboard brakes pressure switch S98.
  3. Pressurize the Right Hydraulic system.
  4. Verifycontinuity between pins 2 and 3 of pressure switch S98.

    1. If there is continuity, replace pressure switch S98.
    2. If there is no continuity, continue with next step.

  5. Verifywiring for a short circuit per the following table:

    From (PRESS SWITCH) Pin To (BCU) Pin
    S98P1 2 A67P1 40
    S98P1 3 A67P1 43

    1. Repair as required.
    2. If wiring is found serviceable, replace BCU.

Registered and/or unregistered trademarks of Bombardier Inc. or its subsidiaries. © 2015 Bombardier Inc. All rights reserved.