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 steering ecu
Components
Removal
Disconnect cable from negative battery
terminal
Remove instrument panel sub-assembly
upper
Remove the instrument panel (see page ip-4).
Remove power steering ecu
Disconnect the 4 connectors.
Remove the 3 nuts and remove the power steering
e ...
Removal
(2005/11-2006/01)
Remove front wheel
Drain automatic transaxle fluid
Drain the automatic transaxle fluid for u140f (see
page ax-147).
Drain the automatic transaxle fluid for u241e (see
page ax-146).
Remove front axle hub nut (see page ah-6)
Disconnect front speed sensor lh (see page
bc-191) ...
Positioning a floor jack
When raising your vehicle with a floor jack, position the jack correctly.
Improper placement may damage your vehicle or cause
injury.
Front
Rear
Caution
When raising your vehicle
Make sure to observe the following precautions to reduce the possibility of
death or serious injury:
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