Removing Wheel Electronics

Information 

• For vehicles with a tire pressure monitoring system, the valve and wheel electronics are only replaced in exceptional cases! The following points can make replacement necessary! 

Valve complete with screw -1 to 7- has to be replaced if:

Fig 1: Identifying Valve And Wheel Electronics With Screw

Courtesy of PORSCHE CARS NORTH AMERICA, INC.

• The wheel electronics unit is removed
• The self-locking -1-  fastening screw is loose
• The bead seat sealing ring -6-  is porous or damaged
• The valve body -7-  is bent
• The union nut -4-  is loose.

The wheel electronics -A-  must be replaced if:

Fig 2: Identifying Wheel Electronics

Courtesy of PORSCHE CARS NORTH AMERICA, INC.

• The housing is visibly deformed
• The filter surface (rectangular or round, porous section on back of wheel electronics unit) is so badly soiled that it can no longer be cleaned by wiping
• Tyre sealant (tire sealing liquid) has been used
• The service life of the battery has expired
• There is a fault within the wheel electronics unit.

After removal of the tire, the wheel electronics -A-  can be seen at the valve in the outer rim well base.

Fig 3: Locating Wheel Electronics Unit

Courtesy of PORSCHE CARS NORTH AMERICA, INC.

1. Release the wheel electronics unit from the valve using a Torx socket screwdriver T 20 (if necessary, counter with a suitable assembly pin, e.g. steel pin Ø approx. 1.8 mm in bore at valve foot) and remove it. The new valve comes with an assembly pin.
   Fig 4: Locating TPM Valve

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.
2. Then unscrew union nut and remove valve.