Purpose/Function
Detects ion generation in the combustion chamber for detecting pre-ignition.
Detects ions which occur due to fuel combustion as current by applying bias voltage to the spark plug, which is amplified in the ignition coil internal circuit and input to the PCM.
Construction
Built into the ignition coil.

Operation
Accumulates the secondary current of the ignition coil in bias condenser (1) and detects ion current (2) by applying the bias voltage to the spark plug.
Pulls in current (4) increased by current amplification circuit (3) to the ignition coil from the PCM.
The PCM measures/converts the current sent to the ignition coil and monitors.

Ion generation mechanism
Ions are generated based on: fuel combustion = chemical reaction / disassociation. The generated negative ions move to the center electrode of the spark plug to which bias voltage is applied, positive ions move to the grounded engine wall surface, and then current flows from the spark plug to the ignition coil.

Fail-safe
Function not equipped.
Ion Sensor Inspection
Lap Pre Tensioner Seat Belt [Two Step Deployment Control System]Air Bag System Service Warnings [Two Step Deployment Control System]
Air Bag Module Inspection
Inspecting an air bag module using a tester can operate (deploy) the air
bag module, which may cause serious injury. Do not use a tester to inspect an
air bag module. Always use the on-board diagnostic function to diagnose the
air bag module for malfunctions ...
Sunroof Switch Inspection
1. Disconnect the negative battery cable..
2. Remove the front map light..
3. Verify that the continuity between the sunroof switch terminals is as indicated
in the table.
If not as indicated in the table, replace the sunroof switch.
...
Energy Absorbing Form Removal/Installation
1. Disconnect the negative battery cable..
2. Remove the seal board upper..
3. Remove the front bumper..
4. Insert the flathead screwdriver shown in the figure, push fasteners A for
back side of front bumper reinforcement arrow shown in the figure.
5. Pull the energy-absorbing form in ...