Kia Carens: Tire Pressure Monitoring System / TPMS Sensor Description and operation

Storage State

Sensors are in this state when they first arrive at dealership.

This state is entered by LF request/command only.

Either LF request / command or an automatic exit due to the pressure will allow an exit from this state.

The transmitter will not transmit RF messages in this state, unless an LF initiate transmission request is received or an exit due to pressure triggers an RF response.

The pressure/temperature measurement rate will be every 60 seconds. 

If four (4) successive pressure measurements exceeding 25 psi are recorded, an exit to the Sleep State will occur.

Sleep State

This state is entered by LF request / command, by exiting from the Rest State following a 15 minute timeout due to no motion  (accelerometer measurement < 10g) or by exiting Storage State due to pressure.

This state is exited by LF request / command or due to motion (accelerometer measurement > 10g).

The transmitter will not transmit RF messages in this state, unless a LF initiate transmission request is received.

Normal Motion State

This state is entered by LF request / command or a return from an alert condition, or by exiting Sleep State due to motion.

This state is exited by LF request / command, no motion or an alert condition.

For the first 80 seconds following Sleep State exit, the transmission rate will be every 16 seconds, the acceleration and pressure  measurement rate will also be at a rate of every 16 seconds for the first 80 seconds after Sleep State exit.

Following the first 80 seconds after Sleep state exit, the transmission rate will be every 1 minute.

The acceleration will be measured every 60 seconds and pressure every 20 seconds following the first 80 seconds after exit from Sleep State.

The transmitter will transition to the Alert State if the temperature exceeds 110C or a 20KPa change in pressure is detected between the last transmitted pressure value and the current measured value.

Rest State

This state is entered by LF request / command or by exiting Normal Motion State State due to accelerometer measurement < 10g.

This state is exited by LF request / command, due to motion (accelerometer measurement > 10g) or following a Rest State timeout of 15 minutes with no motion (accelerometer measurement < 10g) after which it will exist to the Sleep State.

Alert State

This state is entered by LF request/command or a temperature/pressure alert condition (exceeding 110C or a 20KPa change in pressure).

This state is exited by LF request / command or automatically exits once the alert RF transmissions are complete. 

In Alert State pressure measurements occur every 4 seconds and the transmitter will transmit at a 4 second interval for 1 minute.