Toyota prius 3rd gen Weight Detection Sensor Assembly (W1)(W4)(W6)(W7)

Toyota Prius 3 ^rd Generation (XW30)

Toyota Prius 3 ^rd Generation (XW30) Weight Detection Sensor Assembly Wiring Guide: DIY Pinout Diagram

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What is: The Weight Detection Sensor Assembly is the hardware inside the passenger seat that detects seat weight/load, allowing the car’s safety system to decide if and how the passenger airbag should deploy.

1. Introduction

The Toyota Prius 3rd Gen Toyota Prius 3rd Gen Weight Detection Sensor Assembly is a seat-mounted sensor located in the front passenger seat cushion. It measures the occupant’s weight and sends signals to the Occupant Detection ECU, allowing the SRS system to determine airbag deployment—preventing unnecessary or dangerous airbag activation for children or light passengers.

Weight Detection Sensor Assembly – Most Common in (XW30)

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• Components:
• Seat Cushion Sensors– strain gauges or pressure sensors embedded in the seat foam/frame.
• Sensor Wiring Harness – connects sensors to the Occupant Detection ECU.
• Connector Plug – for ECU communication.
• Mounting Brackets/Frame – secures sensors inside the seat.
• Calibration/Signal Module– sometimes integrated to stabilize sensor readings.

2. Weight Detection Sensor Assembly Wiring Diagram & Pinout

A. Connector Location

• Sensor Position: inside the front passenger seat cushion, mounted on the seat frame under the seat foam.
• Connector Type:
  • W1 (3 pin) gray housing
  • W4 (3 pin) black housing
  • W6 (3 pin) gray housing
  • W7 (3 pin) black housing

Weight Detection Sensor Assembly (W1) (W4) (W6) (W7)

W1 TERMINALS OF Rear In Weight Detection Sensor Sub–Assembly CONECTOR

Terminal No	Symbol (Pin Definition)	Wiring (Color Code) & Color	Electrical Paths
1	1	(GR) Gray	➔ W2 5 [Occupant Detection ECU]
2	2	(SB) Sky Blue	➔ W2 9 [Occupant Detection ECU]
3	3	(W) White	➔ W2 3 [Occupant Detection ECU]

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W4 TERMINALS OF Front In Weight Detection Sensor Sub–Assembly CONECTOR

Terminal No	Symbol (Pin Definition)	Wiring (Color Code) & Color	Electrical Paths
1	1	(R) Red	➔ W2 11 [Occupant Detection ECU]
2	2	(P) Pink	➔ W2 7 [Occupant Detection ECU]
3	3	(G) Green	➔ W2 1 [Occupant Detection ECU]

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W6 TERMINALS OF Front Out Weight Detection Sensor Sub–Assemb CONECTOR

Terminal No	Symbol (Pin Definition)	Wiring (Color Code) & Color	Electrical Paths
1	1	(W) White	➔ W2 12 [Occupant Detection ECU]
2	2	(L) Blue	➔ W2 8 [Occupant Detection ECU]
3	3	(LG) Light Green	➔ W2 2 [Occupant Detection ECU]

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W7 TERMINALS OF Rear Out Weight Detection Sensor Sub–Assembly CONECTOR

Terminal No	Symbol (Pin Definition)	Wiring (Color Code) & Color	Electrical Paths
1	1	(V) Violet	➔ W2 6 [Occupant Detection ECU]
2	2	(B) Black	➔ W2 10 [Occupant Detection ECU]
3	3	(BR) Brown	➔ W2 4 [Occupant Detection ECU]

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