02/08/21
Message Overview:
Message Name:
WHEEL SPEED XDCR INBD R/BCU/WRG
Message Code:
3245416HA
Associated CAS:
| Reporting LRU: | Brake Control Unit (BCU) |
| System Description: | 32-43-00 |
| Schematic Diagram: | 32-43-00 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Wiring Diagram: | 32-11-01 [ Global Express ] [ G5000 ] [ Global XRS ] |
Message Description:
Right Inboard Wheel Speed Transducer (WST) has been detected failed by the Brake Control Unit (BCU).
Possible Causes:
- Right Inboard Wheel Speed Transducer (WST) (P18)
- Brake Control Unit (BCU) (A71)
- Associated Wiring
Troubleshooting Tips:
Advisory Wire/Service Bulletin:
- AW700-32-0244 - Operational Procedures to Prevent Freezing Brakes
- AW700-32-0359 - Brake Control System - Data Gathering to Reduce the Brake Control Unit (BCU) No-Fault-Found (NFF) rate
- AW700-32-0513 - Wheel Speed Transducer - Brake System Nuisance Fault Messages
- SB 700-32-016 - MODIFICATION - BRAKE CONTROL SYSTEM - PART NO. CHANGE OF THE BRAKE CONTROL UNIT TO GW415-7125-5
Forum Articles/Infoservice/Newsletter: None
NOTE: If you replace a brake system component please fill out this questionnaire.
Quick Links:
| Removal of the Brake Control Unit | AMM 32-43-01-000-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Installation of the Brake Control Unit | AMM 32-43-01-400-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Removal of the Wheel Speed Transducer | AMM 32-43-53-000-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Installation of the Wheel Speed Transducer | AMM 32-43-53-400-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Functional Test of the Wheel Speed Transducer | AMM 32-43-53-720-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Access to System Diagnostics | AMM 45-45-00-970-804 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Wire Repair - Maintenance Practices - ALL | SPM 20-12-10-02 [ Global Express ] [ G5000 ] [ Global XRS ] |
Troubleshooting Recommendations:
- Re-seat the BCU. Is the fault still present?
- If NO, do close out.
- If YES, continue with next step.
- Perform the Wheel Speed Transducer - Adjustment/Test. Is the fault still present?
- If NO, do close out.
- If YES, continue with next step.
- Disconnect the Right Inboard WST connector (P18). Perform a resistance check as follows:
For P/N: 27700-103
From To Expected Result Result P18-1 P18-2 Must not exceed 700 Ω P18-3 P18-4 Must not exceed 700 Ω For P/N: 27700-105
From To Expected Result Result P18-1 P18-2 650 ±50 Ω P18-3 P18-4 650 ±50 Ω For P/N: 27700-107
From To Expected Result Result P18-1 P18-2 655 ±35 Ω P18-3 P18-4 655 ±35 Ω For P/N: 27700-109
From To Expected Result Result P18-1 P18-2 620 ±55 Ω P18-3 P18-4 620 ±55 Ω NOTE: The resistance check must be performed at 70±5°F(21±3°C). If the temperature is not included in that range, perform the correction of the measurement to 70°F(21°C) with the formulas that follow:
-Resistance value at 70°F=R1 × [(460.1)/(T1 + 390.1)]
-Resistance value at 21°C=R1 × [(255.5)/(T1 + 234.5)]
-T1=Temperature at which it is measured
-R1=Resistance measured at temperature T1- If resistance values are not within tolerance, replace WST and do close out.
- If resistance values are within tolerance, continue with next step.
- Interchange the Right inboard WST with Left inboard WST. Is the fault still present?
- If NO, replace Right inboard WST and do close out.
- If YES, continue with next step.
- Perform wiring checks between the Right inboard WST (P18) and the BCU (A71AP1 and A71BP1).
- If wiring checks are not good, repair defective wiring as required and do close out.
- If wiring checks are good, continue with next step.
- Replace BCU.
- Do close out.