Tire Pressure Monitoring System, Indirect System

Tire Pressure Monitoring System, Indirect System

Tire pressure monitoring is a system that detects slow to moderate reductions in tire pressure at a wheel position. With the help of the ABS sensors, the Tire Pressure Monitoring System (TPMS) compares the speed and rolling circumference of the individuals wheels. If the rolling circumference changes, the tire pressure monitoring indicator in the instrument cluster lights up and a warning tone is heard. On vehicles with a center instrument cluster display, the location of the tire is given.

After changing from run-flat tires (SST) to non-run-flat tires or vice versa the control module must be re-coded.

Rolling circumference of tire may be change if:

• the tire pressure is too low.

• the tire has structural damage.

• the vehicle is loaded on one side.

• the tires on one axle are loaded more heavily (e.g. when towing a trailer or driving up and down inclines).

• the spare tire is installed.

• one tire per axle was changed (or if the tires were rotated from front to back or the other way around).

System Malfunction in TPMS

A system malfunction is stored in the Tire Pressure Monitoring Control Module 2 (J793) and indicated by the constant yellow TPMS lamp in the instrument cluster. The TPMS lamp cannot be turned off by pressing the TPMS button. If there is a DTC memory entry, connect -VAS- -5051 and select "Guided Fault Finding".

Perform Calibration: (readapt tire pressure)

After each change to the tires, the tire pressure monitoring system button in the center console must be pressed while the ignition is switched on and the vehicle is still until the TPMS lamp in the instrument cluster blinks several times. Blinking several times confirms the calibration procedure and the readapting of the tire pressures.