LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Toyota >> 2012 >> Prius Plug-in >> Repair and Diagnosis >> Restraints >> Restraints Control Systems >> Pre-Collision System (Plug-In) (Diagnostic Codes & Circuit Tests) >> Pre-Collision System >> Circuit Tests >> Pre-Collision Brake Cancel Switch Circuit >> Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Pre-Collision Brake Cancel Switch Circuit: Procedure

  1. READ VALUE USING TECHSTREAM (PRE-COLLISION SYSTEM CANCEL SWITCH) 
    1. Use the Data List to check if the pre-collision system cancel switch is functioning properly.
      PRE-COLLISION 2

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Pre-Collision Brake OFF Switch Pre-collision system cancel switch signal/ON or OFF ON: Pre-collision system cancel switch on
      OFF: Pre-collision system cancel switch off      		 -

      OK

      On screen, each item changes between ON and OFF according to above chart.

    NG → See step   2 

    OK → See step   5 

  2. INSPECT PRE-COLLISION SYSTEM CANCEL SWITCH ASSEMBLY 
    1. Remove the pre-collision system cancel switch assembly. Refer to REMOVAL .
      Fig 1: Inspecting Pre-Collision System Cancel Switch Assembly
      GTY334417Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      1 - 2 Pressed Below 1 Ω
      Not pressed 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *a Component without harness connected
      (Pre-collision System Cancel Switch Assembly)
    3. Reinstall the pre-collision system cancel switch assembly. Refer to INSTALLATION .

    NG → See step   6 

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (PRE-COLLISION SYSTEM CANCEL SWITCH - DRIVING SUPPORT ECU) 
    1. Disconnect the pre-collision system cancel switch assembly connector.
    2. Disconnect the driving support ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      L150-1 - L151-5 (PBSW) Always Below 1 Ω
      L150-1 - Body ground Always 10 kΩ or higher
    4. Reconnect the driving support ECU connector.
    5. Reconnect the pre-collision system cancel switch assembly connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (PRE-COLLISION SYSTEM CANCEL SWITCH - DRIVING SUPPORT ECU) 

    OK: Go to next step 

  4. CHECK HARNESS AND CONNECTOR (PRE-COLLISION SYSTEM CANCEL SWITCH ASSEMBLY - BODY GROUND) 
    1. Disconnect the pre-collision system cancel switch assembly connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      L150-2 - Body ground Always Below 1 Ω
    3. Reconnect the pre-collision system cancel switch assembly connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (PRE-COLLISION SYSTEM CANCEL SWITCH ASSEMBLY - BODY GROUND) 

    OK → See step   7 

  5. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE 
  6. REPLACE PRE-COLLISION SYSTEM CANCEL SWITCH ASSEMBLY. Refer to  REMOVAL 
  7. REPLACE DRIVING SUPPORT ECU. Refer to  REMOVAL 
scientia non olet · About LEMON Manuals