Tire Pressure Monitoring System

Components and Component Location

Components

1. ESC Module 2. Cluster 3. TPMS SET Switch

4. Wheel Speed Sensor 5. Tone Wheel

Description and Operation

Description

Indirect Tire Pressure Monitoring System (TPMS): Using the wheel speed signal from the ESC, the system analyzes the tire rolling radius and the change in tire stiffness to determine pressure loss. The TPMS detects under-inflation by calculating pressure loss based on the set pressure. Therefore, the recommended pressure must be re-stored by pressing the SET button after replacing tires or adjusting the tire pressure. Differences between Direct and Indirect TPMS

Indirect TPMS	Direct TPMS
The tire rolling radius and tire stiffness change are calculated indirectly. An air pressure sensor is not required in the wheel. The recommended tire pressure must be re-stored after tire replacement or tire pressure adjustment (by pressing the "SET" button).	Tire pressure inside the tire is measured by a sensor and then transmitted wirelessly to the receiver. Installation of a separate module and four air pressure sensors is required. Low performance may occur due to frequency noise, because direct TPMS uses a wireless transmission method.

Low Tire Pressure Warning Lamp

1. 1
   ON Condition

   • • When the tire pressure is below the allowable threshold
2. 2
   OFF Condition

   • When the low tire pressure warning lamp illuminates due to a rapid leak, the warning lamp will turn off if the tire is inflated above the warning threshold.

Interference with Normal Operation of the Indirect TPMS

Type		Conditions	Symptoms	Possible Cause
Driving conditions	Driving at Low Speed	Continuous driving at speeds below 25 km/h	Warning not issued	Reduced reliability of wheel speed sensor data
	Driving at High Speed	Continuous driving at speeds above 120 km/h	Reduced Performance	Tire Characteristics
	Deceleration/Acceleration	Rapid Acceleration/Braking	Warning Delay	Lack of effective information
Road Condition		Sharp Turns or Winding Roads	Warning Delay	Lack of effective information
Road Surface Conditions		Unpaved or slippery road surfaces	Warning Delay	Lack of effective information
Snow Chains		Snow chains are installed on the vehicle tires.	Warning not issued	Reduced reliability of wheel speed sensor data

Troubleshooting

Troubleshooting

Symptom	Possible Cause	Remedy
The low tire pressure warning lamp illuminates with correct tire pressure / the low tire pressure warning lamp does not illuminate with low pressure.	The SET button was not pressed after tire replacement or tire pressure adjustment.	1 Check the air pressure. 2 Make sure the wheel variant coding procedure is performed correctly. If the code does not match the vehicle specifications, such as wheel size, repeat the procedure. 3 Check the recommended tire pressure and press the SET button. Do not press the SET button without checking the air pressure. The warning lamp may not illuminate when driving with snow chains installed or when driving on unpaved roads.
	The SET button was pressed with incorrect pressure. The SET button was pressed at low pressure without inflating the tire(s) to the specified pressure (regardless of whether the warning lamp is illuminated). The SET button was pressed with tires overinflated or underinflated. The SET button was pressed when there is a significant pressure difference between the tires.
	When driving with snow chains installed
	When driving mainly on unpaved/winding roads

Repair Procedures

Inspection

Indirect TPMS Reset Procedure

1. 1
   Adjust the pressure in all 4 tires to the recommended air pressure.
2. 2
   Press and hold the SET button for more than 3 seconds to store the pressure.
3. 3
   Check that the system warning light flashes for 4 seconds. (Turns off after flashing)
4. 4
   Perform the learning procedure by driving.

Diagnostic Procedure Using Scan Tool

Perform indirect TPMS variant coding using the diagnostic tester when the ESC module is replaced.