Tyre Pressure Monitoring System

 

Welcome to our Tyre Pressure Monitoring System area.

We have provided you with a brief overview about what the Tyre Pressure Monitoring System is, why it is used and how we diagnose and maintain problems with it.

               

If you have any warning lights informing you that there is a fault with a Pressure Sensor please contact us to book a Diagnostic Test so FDS can determine the problem with the sensor. A diagnostic test will be £48, please visit our Diagnostic page for more information on diagnostic testing. If however we find that your vehicle will require a new Pressure Sensor we are able to supply and fit a new one for approx £75. We have also given a list of fault codes (Commonly known as P Codes) that we find when diagnosing faults with the TPMS. 

If you have any questions regarding the Tyre Pressure Monitoring System that is not explained on this page, please Contact us or alternativley you can post us a question on our FAQ page

         

MOT Requirement

From 2013, Tyre Pressure Monitoring Systems (TPMS) will form part of the MOT Test. Vehicles on which Tyre Pressure Monitoring System was originally fitted will have to have it fully operable. When this test is implemented one faulty sensor will result in a fail.

             

What is the Tyre Pressure Monitoring System?

                                    The Tyre Pressure Monitoring System, sometimes known as 'TPMS' 'Tyre Pressure Detector' 'Tyre Deflation Detector' and 'Tyre Pressure Sensor' is an electronic system that has been designed to monitor the air pressure inside the tyres of a vehicle. If a tyre is to become deflated or is failing to monitor the pressure, the Tyre Pressure Monitoring System reports this information to the driver of the vehicle by showing a message stating the nature of the problem on the dashboard via either a warning light or displayed warning message. Each of the sensors transmits the air pressure, temperature, battery information and sensor location to the vehicle’s computer. The Tyre Pressure Monitoring System can help avoid traffic accidents due to under-inflated tyres by early recognition of the problem and can also help to reduce CO2 emissions and reduce tyre abrasion by an optimal inflation.

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The following components are used to monitor the air pressure:

  • Pressure sensor combined with a UHF Transmitter. This is located in the valve of each tyre.
  • HF Reciever. This is in the Tyre Pressure Detection ECU
  • Two Low frequency emitters located on both front wheel arch liners.
  • BSI. This compares the pressure information recieved with pre-programmed units.

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Pressure Sensor

This is designed to transmit the tyre pressure information. There is one of these on each tyre. The electronics are embedded into resin so as to withstand vibrations and power supply is provided via a lithium battery which has an approximate life of 10 years. This is to allow stand alone operation. Transmitter modules are fitted with an inertia switch, this comprises a ball and spring. The inertia switch is able to detect whether the vehicle is driving or stationary as there is a centrifugal force created when the tyre rotates

The Pressure sensor transmits UHF signal that contains:

- Pressure measurement

- Identification code

- Function code

The pressure sensor has two operation modes:

- Driving

- Off (Stationary)

The pressure sensor remains in off mode until the start of driving is detected and will remain in driving mode for as long as the vehicle is moving and for thirty seconds after the vehicle has stopped.

The pressure is sampled:

- Every 10-15 seconds in driving mode

Every 15-16 seconds in off mode

Operation of the pressure sensor:

- Every minute as soon as the vehicle speed is greater than or equal to 20 km/h

Every 60-65 minutes when stationary

- Every 5 seconds maximum if the sampled pressure is abnormal.

The pressure sensor transmits UHF signal to the HF reciever. Signal contains a 45 bit emission frame which consists of the following:

- 4 Start bits

- 1 Seperator bit

- 5 Function codes

- 24 Tyre identification code bits

- 8 Pressure valve bits

- 2 Checksum bits.

HF Reciever

Once the information has been transmitted HF receiver performs the following functions:

- It receives the tyre pressure status information

- It decodes the HF signal 

- It checks the cohernece of the frame received by the pressure sensor

- It validates the frame

- It retransmits the decoded information to the BSI

The HF receiver receives the tyre pressure status information:

- 10 seconds after swtiching the key to the ignition on position if the vehicle is stationary

- Immediately if the vehicle speed is greater than zero

The BSI

The BSI then performs the following:

- Filter the information

- Determine position of the tyre

- Determine pressure of the tyre

- Determines the level of warning

- Controls the warning signal given to the driver either via warning light or displayed message. 

The job of the BSI is to then provide information about position and pressure of the tyre after analysing the frame and using the information is contains. 

Dependent upon the information the BSI will then determine the type of warning that is given:

- A Pressure Warning - This would relate to the tyre pressure status

- An Absence Warning - This would relate to the tyre position status. 

The BSI will then inform the driver of either an abnormal pressure on one of the wheels - from deflation or puncture, or that there is a tyre that is not being monitored. 

Deflated Tyre Detection

After a problem has been determined the tyre deflation detection function provides the information on the status of the tyre, either puncture or deflation. It does this by measuring the tyre pressure using the pressure sensor. The HF Reciever can then transmit the information to the BSI which will ascertain the status of tyre position and pressure. 

Please not that there is not a Tyre Pressure Sensor fitted on your spare wheel

 

Diagnosing the fault 

At FDS we use the latest genuine diagnostic equipment and software for finding a vehicles fault. Below is a list of functions that the diagnostic equipment is able to perform when locating faults with the Tyre Pressure Monitoring System:

- Identification

- Reading faults

- Erasing faults

- Actuator tests

- Parameter measurements

- Configuration

- Programming / Initialisation 

- Download

The diagnostic equipment will locate the fault on the Tyre Pressure Monitoring System and provide us with a 'fault code'. Below is a table of the fault codes that can be picked up in relation to the Tyre Pressure Monitoring System. 

 

TITLE OF FAULT

FAULT CODE
Battery voltage fault P0562
Battery voltage fault P0563
RH Low frequency aerial fault C1600
LH Low frequency aerial fault C1601
ECU Fault P0603
Blank ECU or faulty configuration P0602
Front LH wheel Pressure sensor information fault C1602
Front RH wheel Pressure sensor information fault C1603
Rear LH wheel Pressure sensor information fault C1604
Rear RH wheel Pressure sensor information fault C1605
High frequency remote control fault C1612
The tyre pressure detection is mute U1000
Communication fault on the CAN U1003
No steering wheel information fault U1105
No engine speed information fault U1108
No vehicle speed information fault U1113
No body movement sensor signal fault U1116
Steering wheel angle information fault U1205
Engine speed information fault U1208
Vehicle information speed fault U1213
Body movement sensor signalfault  U1216
Built in Systems Interface (BSI) Information fault U1218
Reception of main wakeup status fault U2000
Remote controlled wakeup line fault U2002
Inconsistency of main wakeup fault  U2003
Transmission of main wakeup status fault U2215