Special Notes For Tyre Pressure Monitoring (TPM)

→ Read and follow the installation instructions for the wheel electronics units. → 443219 REMOVING AND INSTALLING WHEEL ELECTRONICS 

→ Check that the wheel electronics units are assigned correctly.

Information 

• If the old wheels are still in the vicinity after assembly work (for example changing winter tires and/or wheels from another vehicle with TPM), these will still be detected by the system. If one or more of these wheels has a minimum pressure of more than 0.5 bar (7 psi) below the required pressure, this can trigger a warning in the instrument cluster. In this case, remove the other wheels or use the PIWIS Tester to tune the vehicle to be outside the radio range of these wheels. 
• Before changing a tire, read out the remaining life span of the wheel electronics unit (battery capacity) using the PIWIS Tester. 
• For vehicles with a TPM, the valve and wheel electronics unit -A- are only replaced in exceptional cases. The following points can make replacement necessary. 
  Fig 1: Locating Wheel Electronics Unit

  Courtesy of PORSCHE CARS NORTH AMERICA, INC.

Fig 2: Identifying Wheel Electronics Unit Components

Courtesy of PORSCHE CARS NORTH AMERICA, INC.

1. Wheel electronics
2. Valve complete (No. 2 to No. 7)

1. Self-locking (Torx) fastening screw
2. Valve cap (plastic)
3. Valve insert
4. Union nut
5. Washer chamfered on both sides
6. Bead seat sealing ring
7. Valve

• The valve -B- must be replaced if: 
  • The wheel electronics unit -A-  is removed
  • The self-locking fastening screw -1-  is loose
  • The union nut -4-  is loose
  • The valve -7-  is leaking at the valve seat
  • The valve -7-  (valve body) is bent or broken.
• The wheel electronics unit -A- must be replaced if: 
  • The housing is visibly deformed
  • The filter surface (on the bottom) is so soiled that it cannot be cleaned by wiping
  • Tyre sealant (tire sealing liquid) has been used