1.TP(Transponder)
2.Antenna Coil
This wireless communication runs on Radio frequency. The antenna coil is mounted on the top of ignition lock for RF transmission and receiving. The RF signal from the transponder received by the antenna coil is converted into messages for serial communication by the Immobilizer unit. And the received messages from the ECM are converted into an RF signal, which is transmitted, to the transponder by the antenna. Coil antenna provides energy to the transponder key and retrieves signal from the transponder and send it to Immobilizer unit.
The PCM/ECM sets DTC if there is any open or short circuit between the antenna coil and Immobilizer unit
Item
Detecting Condition
Possible Cause
DTC Strategy
Data status receiving from transponder
Open or short circuit in antenna coil
Faulty antenna Coil
Faulty ICU
Threshold value
Open or Short circuit
Detecting time
1 time
DTC Erasing
Condition
Without a fault during 30 trips or using a GDS
Fig.1) A normal signal waveform of antenna and immobilizer communication when IG key(TP: Transponder) is OFF to ON.