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Home >> Toyota >> 2012 >> Prius V >> Repair and Diagnosis (Single Page) >> Restraints >> Restraints Control Systems >> Pre-Collision System [Diagnostics - Introduction] >> Pre-Collision System >> Problem Symptoms Table >> Problem Symptoms Table
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Problem Symptoms Table

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PRE-COLLISION SYSTEM

Symptom Suspected Area See
System does not operate normally even when DTCs are not output Power source circuit Refer to Power Source Circuit
Seat belt warning system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Pre-collision brake cancel switch circuit Refer to Pre-Collision Brake Cancel Switch Circuit
Front seat inner belt assembly RH Refer to REMOVAL
Front seat inner belt assembly LH Refer to REMOVAL
Seat belt control ECU Refer to REMOVAL
Only pre-collision brake operation is not performed Pre-collision brake cancel switch circuit Refer to Pre-Collision Brake Cancel Switch Circuit
Seat belt control ECU Refer to REMOVAL
Driving support ECU assembly Refer to REMOVAL
Skid control ECU Refer to REMOVAL
Although there is no possibility of collision, pre-collision controls (all front collision controls) operate Proceed to "Cases of Unnecessary Pre-collision System Operation" (Although there is no possibility of collision, the millimeter wave radar sensor detects an object and activates the pre-collision system) Refer to SYSTEM DESCRIPTION 
Check installation condition of millimeter wave radar sensor Refer to INSTALLATION
Perform millimeter wave radar sensor adjustment Refer to ADJUSTMENT
Millimeter wave radar sensor Refer to REMOVAL
Seat belt control ECU Refer to REMOVAL
Driving support ECU assembly Refer to REMOVAL
Although there is possibility of collision, pre-collision controls (all front collision controls) do not operate Pre-collision brake cancel switch circuit Refer to Pre-Collision Brake Cancel Switch Circuit
Vehicle condition/environment does not match pre-collision control operation conditions (Confirm control operation conditions) Refer to SYSTEM DESCRIPTION 
Check installation condition of millimeter wave radar sensor Refer to INSTALLATION
Perform millimeter wave radar sensor adjustment Refer to ADJUSTMENT
Millimeter wave radar sensor Refer to REMOVAL
Seat belt control ECU Refer to REMOVAL
Driving support ECU assembly Refer to REMOVAL
Pre-collision system OFF (pre-collision brake) does not operate LED (perform Active test) Refer to DATA LIST / ACTIVE TEST
Pre-collision brake cancel switch circuit Refer to Pre-Collision Brake Cancel Switch Circuit
Seat belt control ECU Refer to REMOVAL
Meter circuit plate Refer to DISASSEMBLY
Skid control ECU Refer to REMOVAL
Only pre-collision seat belt does not operate Buckle switch error (malfunction in which DTC is not output) -
Seat belt control ECU Refer to REMOVAL