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Home >> Toyota >> 2012 >> Sienna XLE, AWD >> Repair and Diagnosis >> Engine Performance >> Ignition System >> Smart Key System (For Start Function) (Diagnostic Codes & Symptom Tests) >> SMART KEY SYSTEM (for Start Function) >> Symptom Tests >> Engine does not Start >> Inspection Procedure
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Inspection Procedure

NOTE:
  • When using the Techstream with the engine switch off, perform either of the following: 1) Turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the Techstream and vehicle begins, or 2) connect the Techstream to the vehicle, select the vehicle type under manual mode, and then enter the following menus: Body Electrical / Smart Key / Trouble Codes.
  • The smart key system uses multiplex communication. First perform the inspections in "How to Proceed with Troubleshooting" to confirm that there are no communication malfunctions before proceeding with troubleshooting. Refer to HOW TO PROCEED WITH TROUBLESHOOTING .
  • If the smart key system is disabled through the customize function, enable the system before performing troubleshooting. Refer to CUSTOMIZE PARAMETERS .
  • Inspect the fuses of circuits related to this system before performing the following inspection procedure.
  • When replacing the steering lock actuator assembly (steering lock ECU), certification ECU, registration must be performed. Refer to REGISTRATION .
  • If the steering lock actuator assembly (steering lock ECU) is replaced, be sure to confirm that the steering lock is unlocked by turning the steering wheel to the left and right before starting the engine. If the steering lock is locked for any reason, open and close a door with the engine switch off, and then unlock the steering lock by pressing the engine switch. This prevents the engine from starting while the steering lock is locked.
  • After completing repairs, confirm that the problem does not occur.

HINT: 

RELATED DATA LIST AND ACTIVE TEST ITEMS

Problem Symptom Data List Item Active Test Item
Engine does not start Power Source Control 
  • Power Supply Open
  • Starter SW
  • Stop Light Switch1
  • Steering Unlock Switch
  • Power Supply Condition
  • IG1 Relay Monitor(Inside)
  • IG2 Relay Monitor(Inside)
  • IG1 Relay Monitor(Outside)
  • IG2 Relay Monitor(Outside)
  • Latch Circuit
  • Shift P Signal
  • Neutral SW/ Clutch SW
  • Starter Request Signal

Smart Key 
  • S Code Check
  • L Code Check
  • Engine Start Request
  • Immobiliser

Starting Control 
  • Ignition
  • Shift Position P or N
-

HINT: 

If the brake pedal is repeatedly depressed while the engine is stopped, the brake booster pressure is released and the force required to depress the brake pedal to illuminate the stop lights increases.