GEAR DISAGREE
(Caution)

The amber 'GEAR DISAGREE' caution CAS message indicates that the gear position and the landing gear switch position do not match.

• The PSEU has detected a discrepancy between gear commanded position and actual position, these indications are caused by the following situations:

1. The landing gear does not reach position that agrees with the control handle within maximum swing time-out.
2. A landing gear fails to move when commanded (similar to swing time-out, shorter limits).
3. Uncommanded movement of a landing gear.

Caution will not be present when fault is detected in an up-lock sensor.

• Gear System Block Diagram
  

  

• PSEU non-volatile memory can be downloaded from the MDC for additional trouble shooting information and faults.
• Advisory Wire 300-32-0084 may provide some relevant information with aircraft that have recently replace the NLG "down & lock" proximity switches PX10 and PX40.

• Proximity Sensors
• Proximity Sensor Electronic Unit (PSEU) (A9)
• Associated Wiring

Advisory Wire/Service Bulletin:

• AW300-32-0084 - Nose Landing Gear Downlock Proximity Sensor Installation
• AW300-32-0255 - Data collection for the PSEU Failure

Forum Articles/Infoservice/Newsletter: None

NOTE: If the PROX SYS FAULT (Advisory) CAS message is present at the same time, use SmartFix Plus (SFP) to troubleshoot that message first.

1. Use the MDC to view the GEAR SENSOR STATUS MENU as per AMM task 32-61-00-820-801 and adjust any sensor out of tolerance.
   
2. Visually inspect and adjust the proximity sensor switches IAW AMM TASK 32-61-00-820-801, to correct a specific gear disagreement, check and adjust the relevant switches per AMM TASK 32-61-00-710-801, then perform the system functional test of the proximity sensors IAW AMM TASK 32-61-00-720-801.

• The down and lock switches are as follows: NLG (PX10, PX40) Left MLG (PX09, PX39) Right (PX08, PX038).
  

  

• The up and lock switches are as follows: NLG (PX06) Left MLG (PX05) Right MLG (PX04).
  
  

Select an MDC Fault Code/Message:B3-007642 - LEFT GEAR NO MVT [PSEU LRU]B3-007643 - RIGHT GEAR NO MVT [PSEU LRU]B3-007644 - NOSE GEAR NO MVT [PSEU LRU]B3-007645 - LEFT GEAR TIME EXCEEDED [PSEU LRU]B3-007646 - NOSE GEAR TIME EXCEEDED [PSEU LRU]B3-007647 - RIGHT GEAR TIME EXCEEDED [PSEU LRU]B3-007648 - LG UNCOMMANDED MVT [PSEU LRU]B3-007649 - NG UNCOMMANDED MVT [PSEU LRU]B3-007650 - RG UNCOMMANDED MVT [PSEU LRU]