Introduction

The mandatory rule of TPMS on passenger car has not been news anymore since 2014 in the world. The news shall be the rule making of TPMS on truck and bus. In this respect, there is great interest what is the system configuration and the fitment method of CV TPMS.

For example, the questions are :

• ⋅ Should it be the internal sensor types same as passenger car?
• ⋅ How to mount it?

The configuration of CV TPM system should overcome the several challenges :

• ⋅ The wide range of vehicle and rims
• ⋅ The large size of vehicle against limited radio wave transmissibility
• ⋅ The mounting of tire sensor
• ⋅ The solution of tire localization and initialization
• ⋅ The need of temperature information

To overcome these challenges, SEETRON had co-development project with HYUNDAI motors during 2007 to 2010 and developed the most advanced CV TPMS. SEETRON has supplied these leading-edge CV TPMS technologies to HYUNDAI motors as tier 1 supplier of original equipment manufacturer since 2012.

The SEETRON CV TPMS has been equipped to the tractor and cargo truck, model XCIENT, the tour bus, model UNIVERSE, of HYUNDAI motors and the tour bus, model GRANBIRD of KIA motors, etc.

System overview

The system consists of TPMS ECU and 1~3 antenna module slaves and tire sensor of same number of tires.

The outstanding feature

The TP2-OEM goes where no other TPM system has goes before.

- The auto location of each tire
- Initialization by auto-learning
- Auto pairing function of multiple antenna module
- Parking supervision
- Auto coupling of trailers
- Data communication by CAN SAE J1939 or serial

Specification of system

Description
Tire Sensor	Radio Frequency
	Modulation Type
	Mounting
	Operation Temperature
	Battery Life
ECU/Antenna module	Configuration
	Data communication
TPMS HMI

Specification	Remarks
433/315 MHz	Regulation spec.
FSK
Valve type
-40℃ ~ +125℃
5 years	Normal condition
TPMS ECU 1 Slave 1~3
ECU to HMI : CAN J1939 ECU to Slave : LIN	CAN 250 Kbps
Multi display & Telltale	Meter cluster

The mounting of tire sensor

Internal fit of tire sensor

The best solution of OE tire sensor is the internal valve type and the basic concept is same as the tire sensor of metal clamp valve of passenger car. It can avoid any problem during demounting process and it has been tested on the full automatic tire mounting line.
A weak point is that there are many different tire valves.
However, SEETRON had designed the segmented tire sensors against all kind of rim and tire valves.
SEETRON is ready to support all kind of rims and valves including large bore.

TPS-V3-20-6

TPS-V3-21-9

TPS-55MS-00N

TPS-TR545D

The unique valve-system type design

The advantage of unique valve stem sensor is:
- Easy to mount (just same as conventional tire valve stem mounting)
- Robust design
- No breakage during demounting
- Simple to fit (Loosen and Drop)
- Real monitoring of temperature inside tire
- Versatility for all kind of rims (17.5”, 19.5”, 22.5”, wide base rim).

Tire Pressure Sensor(TPS)

picture 1 outside position value installation

picture 2 inside position value installation

Specification of Tire Sensor

Item	Description
Pressure	Operation Range
	Resolution
Temperature	Operation Range
	Resolution

Specification	Remarks
100kPa~1400kPa (0 ~ 13 bar)
5.5kPa/bit (1psi = 6.895kPa)
-40℃ ~ 125℃
1℃/bit

TPMS ECU and Antenna-modules

The TPMS consists of one TPMS ECU, 1-3 antenna-module slave and tire sensors of same number of tires. The TPMS ECU is used to locate around the cabin. TPMS ECU keeps Tire sensor ID and does the localization and initiation by auto learning or Manual-teach-in, parking supervision, and sends DTC. It has the CAN communication to the vehicle CAN and LIN communication with the antenna module slaves.
The antenna module slave is used to locate on the front area of side frame or on the side frame of chassis. It has very simple functions: RF receiver and LIN communication. The AM-S enclosure has same shape of TPMS ECU. It is very compact and very rigid enclosure. The housings and connectors are water and shock proof to prevent any damage from the exposed position.

Specification of ECU/Antenna-module

Description

Description	Specification	Remarks
Power supply	DC 24V
Operation Voltage	DC 9 – 36 V
Operating Temperature	-40℃ ~ 85℃
Radio Frequency	433/315 MHz
Modulation	FSK
Sensibility	-105 dB
Size (L x H x W)	117*69*39.2 mm
COMM. SPEC. (Master-Slave)	LIN 1.3 , 10kbps
COMM. SPEC.(Master-Vehicle CAN)	J1939 (CAN 2.0B, 250kbps)

HMI

The OE clusters have been developed by truck and bus manufacturers and it shows the tire pressure and temperature and warns of low pressure and high temperature during driving.

TP2-OEM for passenger car

Based on the after-market sales experience since 2006 and CV-OEM, the OEM products for passenger cars are available. The concept of unique valve design has been transferred to the swivel tire sensor of passenger car TPMS. This swivel tire sensor can be able to work to 12 - 24 inches rim and it has the most-wide angle in the world. The TP2-OEM-PC can afford the FMVSS 138 of NAFTA, ECE-R64 of Europe and Korean regulation.