Basic Function Of Tire Pressure Loss Detection System - GF40.15-P-9900A
Model all (4xWD, CAR)
Overview
This document contains information on:
- General
- Function
- Indirect measuring procedure
- Direct measuring procedure
General
The tire pressure loss warning system monitors and continuously checks the given tire pressure during vehicle operation. If a pressure drop occurs in the wheel and tire assemblies, a warning is issued via the driver's display.
Function
The tire pressure loss warning system detects a significant pressure loss at the tires. Before damage to the tire occurs, the driver is informed via a message in the driver's display. As an output parameter for determining the tire pressure loss, the signals from the rotational speed sensors are used, for example, which evaluate the ESP® control unit. In contrast to the tire pressure monitoring system, the tire pressure loss warning system is an indirect measurement system.
Indirect measuring procedure
In the indirect measuring procedure, the tire pressure is read out via the rotational speed sensors of the ABS. These detect a change in tire diameter when the tire pressure decreases, in which case the rotational speed of the affected wheel and tire assembly increases in relation to the other. This increase in rotational speed is then interpreted as a pressure drop.
Direct measuring procedure:
The tire pressure monitoring system monitors the air pressure in the individual tires by comparing the measured pressure with a previously stored reference pressure. With this direct measuring procedure, the tire pressures are measured directly via sensors in the valves of the wheel and tire assemblies. This allows the exact tire pressure from each wheel and tire assembly to be read out via the instrument cluster.
| Additional basic functions | |||
| Tire pressure monitoring system, basic function | Model all (CAR) with code 475 (Tire pressure monitor (TPM)) | GF40.15-P-1000A | |
| Tire pressure loss warning system, basic function | Model all (CAR) with code 477 (Tire pressure loss warner) | GF40.15-P-1001A | |
| Component descriptions | |||
| Component description for tire pressure monitor control unit | Model 223 with code 475 (Tire pressure monitor (TPM)) | GF40.15-P-5124A | |
| Model 243 | GF40.15-P-5124B | ||
| Model 206 | GF40.15-P-5124C | ||
| Model 297 | GF40.15-P-5124D | ||
| Model 295 | GF40.15-P-5124E | ||
| Model 232 | GF40.15-P-5124F | ||
| Tire pressure sensor, component description | Model 223 | GF40.15-P-5130A | |
| Model 206 | GF40.15-P-5130C | ||
| Model 297 | GF40.15-P-5130D | ||
| Model 295 | GF40.15-P-5130E | ||
| Model 232 | GF40.15-P-5130F |