The engine immobiliser system is designed to prevent the vehicle from being stolen. This system uses a transponder key ecu that stores the key codes of authorized ignition keys. If an attempt is made to start the engine using an unauthorized key, the ecu sends a signal to the ecm to prohibit fuel delivery and ignition, effectively disabling the engine.

The transponder key coil receives this signal, the transponder key amplifier amplifies it, and then the signal is transmitted to the ecu. The ecu matches the key's id code with the vehicle's id code, which was previously registered in the ecu and then communicates the results to the ecm using sfi communication.
Engine immobiliser system
How to proceed with troubleshootingPower seat switch
Inspection
Inspect front power seat switch
Measure the resistance between the terminals when
each switch is operated.
Standard resistance
Slide switch
Front vertical switch
Lifter switch
Reclining switch
If the result is not as specified, replace the switch. ...
Checking the coolant
The coolant level is satisfactory
if it is between the "FULL" and
"LOW" lines on the reservoir
when the engine is cold.
Reservoir cap
"FULL" line
"LOW" line
If the level is on or below the "LOW" line, add coolant up to the "FULL"
line.
â– Coolant selection
Only use "Toyota Super Long Life
Cool ...
Solar sensor (for automatic air conditioning system)
Components
Removal
Disconnect cable from negative battery
terminal
Caution:
Wait at least 90 seconds after disconnecting the
cable from the negative (-) battery terminal to
prevent airbag and seat belt pretensioner activation.
Remove solar sensor
Using a screwdriver, p ...