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Home >> Toyota >> 2012 >> Matrix S, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 7 (Engine Immobilizer System (W/Smart Key) (Diagnostics - Introduction)) >> ENGINE IMMOBILIZER SYSTEM (w/ Smart Key System) >> System Diagram >> System Diagram
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System Diagram

WARNING: This page is about a different car, the 2011 Toyota Corolla. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Engine Immobilizer System Diagram (W/ Smart Key System)
GTY198038Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
COMMUNICATION TABLE

Transmitting ECU (Transmitter) Receiving ECU (Receiver) Signal Communication Method
Steering lock ECU
  • Certification ECU (Smart Key ECU Assembly)
  • ID code box (Immobilizer Code ECU)
Steering lock request signal LIN
Steering unlock signal
Steering lock confirmation signal
Steering unlock confirmation signal
Diagnosis response signal
Steering unlock drive relay signal
Steering lock drive relay signal
Steering lock motor operation signal
ID code box (Immobilizer Code ECU) Certification ECU (Smart Key ECU Assembly) Matching request random number signal LIN
EEPROM access malfunction signal
Model code matching signal
Model code mismatching signal
ECM code receiving status signal
Engine start permission request signal
Engine start permission response signal
S code matching result signal
S code registration status signal
S code registration mode signal
L code matching result signal
ECM communication signal
Registered key number response signal
Diagnosis mode switching signal
DTC (B2791) signal
Registered key number signal
ID code box (Immobilizer Code ECU) Steering lock ECU Steering lock release signal LIN
Matching request random number signal
Certification ECU (Smart Key ECU Assembly) ID code box (Immobilizer Code ECU) 3 bit code request signal LIN
ID code matching result signal
Registered key number signal
Vehicle type handle signal
Certification ECU (Smart Key ECU Assembly)
  • ID code box (Immobilizer Code ECU)
  • Steering lock ECU
L code registration mode signal LIN
Diagnosis mode request signal
DTC clear request signal
L code registration status signal
Main body ECU (Instrument panel junction block) Certification ECU (Smart Key ECU Assembly) Key code recognition signal LIN