GF40.15-P-0001-05RE Tire Pressure Monitor (TPM), Messages Relevant to Operation
GF40.15-P-0001-05RE Tire pressure monitor (TPM), messages relevant to operation
- with CODE (475) Tire pressure monitor (Siemens)
- except CODE (494) USA version
- except CODE (498) Japan version
- as of 1.6.05 up to model year 08
Tire pressure monitoring (TPM) assists the driver in constantly monitoring the correct tire inflation pressure.
Messages relevant to operation in the left multifunction display (A1p13) of the instrument cluster (A1) inform the driver that the air pressure in at least one wheel is changing or has changed. The messages ensue in "yellow" (information messages) or in "red" (warning messages).
When "red" warning messages appear, the tire pressure monitor warning lamp (A1e66) in the instrument cluster is activated. Messages relevant to operation are stored in the TPM [RDK] control unit (N88) with an event code.
Messages relevant to operation describe a regular operating condition. In the event of complaint there is no reason to exchange TPM system components.
Information messages
If the tire inflation pressure drops by 0.25 bar below the pressure set by the driver and stored in the TPM [RDK] control unit for more than 12 minutes (in one wheel or several wheels), this is displayed on the left multifunction display (A1p13) and right multifunction display (A1p15) without specifying the tire location.
After the end of the trip with ignition "OFF" (circuit 15) the need for pressure correction is pointed out. The driver is then requested to check the tire inflation pressures of all wheels, correct them if necessary and then reactivate the TPM system.
This message is self-acknowledging. It disappears after 30 seconds if it is no longer actuated.
A plausibility check on the pressure values is carried out as follows:
^ All tire pressures are above the minimum pressure specified for the model series.
^ The difference between the highest and lowest pressure value is 1.5 bar max.
^ The pressure difference between the right and left side of an axle is a maximum of 0.5 bar.
^ The rear axle tire pressures may deviate from the average pressure on the front axle by 0.5 bar max.
Rapid pressure loss (more than 0.2 bar/min) was detected.
The driver is requested to stop the vehicle immediately and to check all tires for foreign bodies which may have penetrated.
In addition the tire pressure monitor warning lamp in the instrument cluster is actuated.
To make the vehicle safe to drive the spare tire is to be fitted if necessary or TIREFIT tire repair kit used.
The appropriate TPM wheel sensor must be replaced after the use of a TIREFIT tire repair kit.
A rapid pressure loss (more than 0.2 bar/min) has been detected in the wheel (rear right) (shown for a pressure loss in the right rear tire).
The driver is requested to stop the vehicle immediately and to check all the tires for any foreign bodies which may have penetrated.
In addition the tire pressure monitor warning lamp in the instrument cluster is actuated.
To make the vehicle safe to drive the spare tire is to be fitted if necessary or TIREFIT tire repair kit used.
The appropriate TPM wheel sensor must be replaced after the use of a TIREFIT tire repair kit.
A pressure loss of greater than 20 % or 0.5 bar is detected and the wheel position is not assigned.
In addition the tire pressure monitor warning lamp in the instrument cluster is actuated.
The TPM [RDK] control unit has stored the air pressure of the tires in each case as the specified pressure to be monitored.
Even when the tire inflation pressures have been corrected in the workshop a warning message appears with ignition "ON" (circuit 15).
The TPM [tire pressure monitor] system must be reactivated.
On new vehicles at the plant the TPM system is activated with an increased tire inflation pressure (approx 3.5 bar).
Possible cause:
If at the preceding ignition "ON" (circuit 15) a "red" warning message was issued, then the "yellow" system message shown opposite is displayed even when ignition is switched "ON" repeatedly (circuit 15), as long as the TPM system has not been reactivated.
In a parallel operation the system activates the tire pressure monitor warning lamp in the instrument cluster.
Here wheels without TPM wheel sensors have been installed.
The TPM system is faulty.
Possible cause:
^ Over/under voltage
^ Interference transmitter
The TPM system is temporarily inactive.
Possible causes:
^ Spare tire without TPM wheel sensor
^ Battery (TPM wheel sensor) empty
^ TPM wheel sensor faulty
^ Overtemperature (TPM wheel sensor)
The driver has carried out reactivation via the operating menu in the instrument cluster.