GF40.15-P-2004RT Detecting Rapid Pressure Loss, Function

GF40.15-P-2004RT Detecting rapid pressure loss, function
- with CODE (475) Tire pressure monitor (Siemens)
- up to model year 08


Function
Driving safety is no longer guaranteed if there is a rapid pressure loss. If, while driving, a progressive pressure loss over a specific period is determined, then one must assume that a tire is defective. In such an instance a warning (for t = 60 s after the start of the pressure loss > 0.25 bar/min or 3 psi/min) is triggered, before the trigger criterion for the hard warning has been reached.

If the TPM [RDK] control unit (N88) detects that a rapid pressure loss (> 0.25 bar/min or 3 psi/min) occurs at one wheel, a "hard warning" ("red" display) is issued.

The "hard warning" continues to be displayed as long as circuit 15 "ON" is switched on.

When circuit 15 "ON" is switched on again a "soft warning" is issued.

A "soft warning" is repeated at each engine start, if the tire pressure monitoring TPM [RDK] system is not reactivated.

The tire pressure monitor warning lamp (A1e66) in the instrument cluster (A1) is activated at the same time as the "hard warning". Following successful inflation detection or manual reactivation the warning is then cleared.

The driver is responsible for deciding whether to continue driving at low speed to the next specialist workshop or whether a repair (fitting the spare wheel or using TIREFIT) is necessary on site.

For USA version, code 494, TIREFIT is not used.