gf4015p2001rt

Detecting seeping pressure loss, function

Type gf · topic 40.15 · version 0103 · 2008-03-25

Applies to: MODEL 251.1 with CODE (475) Tire pressure monitor (Siemens) up to Model Year 8 MODEL 251.0 with CODE (475) Tire pressure monitor (Siemens) up to Model Year 8

Where it sits

Function group 2 Chassis › 40 Wheels, chassis alignment check › 40.15 Tire pressure/tire pressure monitoring — Series 251 (models 0**, 1**)

GF40.15-P-2001RT

Detecting seeping pressure loss, function

20.5.05

MODEL 251.1
with CODE (475) Tire pressure monitor (Siemens)
up to Model Year 8

MODEL 251.0
with CODE (475) Tire pressure monitor (Siemens)
up to Model Year 8

Function

The "soft warning" operating mode is characterized by a minimum tire pressure at which the vehicle can continue to be driven safely. The driver is requested to correct the tire inflation pressure at the next opportunity via the multifunction display (A1p13) in the instrument cluster (A1). A "soft warning" is triggered if the temperature-evaluated tire inflation pressure is
> 0.25 bar or 3 psi lower than the stored set value.

This is done for the first time with circuit 15 "ON" and is displayed immediately after a journey has been completed. The driver is then asked to check the tire inflation pressure and correct it if necessary.

Diffusion causes each tire to lose air through the course of time and thus it is also shown as a "soft warning".

This information with regard to the pending correction of the tire inflation pressure is sent to the driver in good time as a convenience feature.

Following successful inflation detection or manual reactivation the warning is then cleared.

If the temperature-weighted tire inflation pressure is
> 0.5 bar or 7 psi lower than the stored set pressure, a "hard warning" ("red" display) is issued.

Tire pressure monitor control unit, component description

GF40.15-P-5124RT

Referenced documents