Tire pressure monitor (TPM [RDK]) messages - GF40.15-P-0001-08LEA
The messages from the tire pressure monitor (RDK) system are shown in the multifunction display (A1p13) in the instrument cluster (A1). Depending on the warning message, the tire pressure monitor warning lamp (A1e66) is also continuously actuated.
On vehicles with code (494) USA version, the tire pressure monitor warning lamp in the instrument cluster will flash for t = 60 s if there is a malfunction in the tire pressure monitoring system. Then it will be actuated permanently.
There is a distinction between the two following types of message in the multifunction display on the instrument cluster:
- Menu displays
- Warning messages
The menu displays can be called up in the service menu and tire pressure submenu in the multifunction display in the instrument cluster using the system selection button (S110s3) and scroll forward and back button (S110s1) in the left multifunction steering wheel button group (S110).
Warning messages are issued automatically.
Menu display 1
Status picture of TPM [RDK] system after ignition restart (Status "Circuit 15 ON"). No high frequency signals (433 MHz) from the left front TPM wheel sensor (A69/1), right front TPM wheel sensor (A69/2), left rear TPM wheel sensor (A69/3) and right rear TPM wheel sensor (A69/4) are available yet. When the wheels are already known to the system, the pressure picture appears shortly after the start of a trip. It can take a few minutes until the position identification is learnt with new wheels.
A manual restart is possible by pressing the scroll forward and back button in the lower subfield and then the OK button (S110s6).
Menu display 2
Normal condition of TPM system (pressure display).
A manual restart is possible by pressing the scroll forward and back button in the lower subfield and then the OK button.
Menu display 3
Status picture of TPM system with manual restart by pressing the scroll forward and back button in the lower subfield and then the OK button.
Menu display 4
The transmitter key (A8/1) in the EZS control unit (N73) has only been turned from position "Circuit 15C ON" to position "Circuit 15R ON". The TPM [RDK] system is not available until status "Circuit 15 ON".
Menu display 5
Status picture in event of fault, the TPM system is nonfunctional. Possible causes are:
- System shutoff due to fault (diagnosis fault entry) or TPM [RDK] control unit (N88) nonfunctional (shutoff due to malfunction)
- Temporary fault (overvoltage/undervoltage, radio interference)
- The instrument cluster does not receive any messages from the TPM [RDK] control unit
Menu display 6
Status picture in event of missing wheel sensors or if TPM [RDK] control unit is not receiving any high frequency signals (433 MHz) from wheel sensors.
Probable cause, wheels without wheel sensors are fitted.
Menu display 7
Status picture when "commissioning" the TPM system with the diagnostic system.
Warning message 1
Status picture in event of fault, the TPM system is nonfunctional. The instrument cluster does not receive any messages from the TPM [RDK] control unit because at least one of the following possible causes exists:
- No TPM [RDK] control unit
- TPM [RDK] control unit is defective
- Control Area Network (data bus/CAN bus) (CAN) line interrupted
On vehicles with code (494) USA version, the tire pressure monitor warning lamp in the instrument cluster flashes for t = 60 s. Then it will be actuated permanently. Following the next ignition sequence, this procedure will repeat itself until the fault is eliminated.
Warning message 2
"Soft warning" caused by one of the following reasons:
- There is a pressure loss of p > 0.25 bar. At the end of the trip (status "Circuit 15 OFF"), the system informs the driver that pressure correction is necessary. No wheel is highlighted because normally all tire pressures have to be corrected.
- On vehicles except code (494) USA version, the message appears after a few minutes of driving after automatic filling detection if the new pressure values are implausible.
Warning message 3
"Hard warning" with position specified, if one of the following conditions is present:
- Pressure loss while driving of 20 % or p0.5 bar if wheel positions are identified
In addition the tire pressure monitor warning lamp in the instrument cluster is actuated continuously.
Warning message 4
"Hard warning" without position specified, if one of the following conditions is present:
- Pressure loss of 20 % or p0.5 bar if wheel positions are not identified (vehicle at standstill with circuit 15 ON)
In addition the tire pressure monitor warning lamp in the instrument cluster is actuated continuously.
Warning message 5
"Hard warning" in event of leak detection (rapid pressure loss) at a tire, with position specified, if one of the following conditions is present:
- Pressure loss while driving of p > 0.1 bar/min if wheel positions are identified
In addition the tire pressure monitor warning lamp in the instrument cluster is actuated continuously.
Warning message 6
"Hard warning" in event of leak detection (rapid pressure loss) at a tire, without position specified, if one of the following conditions is present:
- Pressure loss while driving of p > 0.1 bar/min if wheel positions are not identified
In addition the tire pressure monitor warning lamp in the instrument cluster is actuated continuously.
Warning message 7
Status picture in event of missing wheel sensors or if TPM [RDK] control unit is not receiving any high frequency signals (433 MHz) from wheel sensors.
Probable cause, wheels without wheel sensors are fitted.
Warning message 8
The TPM system is temporarily inactive because at least one of the following possible causes exists:
- Interfering transmitters in vicinity
- Overvoltage or undervoltage present
In this case, a repair is not required for the defect.
Warning message 9
The TPM system does not receive all the high frequency signals (433 MHz) from the wheel sensors because at least one of the following reasons exists:
- Individual wheel sensors missing, the remaining wheels can still be monitored. The TPM [RDK] control unit only receives high frequency signals (433 MHz) from the left front TPM wheel sensor, right front TPM wheel sensor and left rear TPM wheel sensor
- Spare tire without wheel sensor fitted
- Wheel sensor defective
- Battery of respective wheel sensor empty
- Overtemperature of respective wheel sensor
Warning message 10
Operating feedback after manual restart by pressing the scroll forward and back button in the lower subfield and then the OK button with "Menu display 3". The current tire pressures are adopted as specified pressures (specified values) for each tire.