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



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


Function

If progressive pressure loss is detected during a certain period (gradient) of time while driving, it is assumed that a tire is defective. In this case a warning is issued even before the triggering parameter for the hard warning has been reached. As a rule the warning is issued 60 seconds at the most after the start of a pressure loss of greater than 0.2 bar/min and is shown in the left multifunction display (A1p13) in the instrument cluster (A1) as the warning message (red) "Caution, tire defect".

Cancellation condition

The warning can be canceled during the ignition sequence by successful filling detection or manual reactivation. When the engine is switched back on after a leak warning the tire pressure monitor warning (A1e66) in the instrument cluster is initially activated. If there are new pressure values and none of the warning criteria are fulfilled after driving has started the tire pressure monitor warning lamp is switched off and the warning message is canceled. The warning is canceled when filling detection or a manual reactivation is successfully carried out.