Transponder Coil
WARNING: This page is about a different car, the 2006 Dodge Viper. However, it is still accessible from the selected car via links, so may be relevant.
A transponder coil is packaged in the transmitter, which can also be used to reprogram the TPM. This is achieved by using a low frequency activation/receiver device designed for 125 kHz to activate the transmitter electromagnetically. The activation/receiver device can also be used for read back of the wheel pressure. The coil field must be applied for six seconds in order to read the current tire air pressure.