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Fitting of TPMS Sensors into Wheels
Introduction
There are 3 main types of TPM sensor mounting arrangement to the wheel rim.
Snap fit / Pull Through sensor
Schrader based TPM electronics with a pull through fitting which needs no special equipment to install other than a standard rubber stem puller.
Clamp in / Bolt in sensor
Most popular type of fitting adopted by most manufacturers. Usually requires a dynamic programmable torque wrench or torque profiling gun to mount. Additionally, may also require a mounting jig to assist with the installation and ensure the parts are fitted at the correct angle and a good seal is formed without breakage. Some manufacturers specify a particular torque profile and torquing process be applied to ensure a good residual torque.
Ford Banded sensor
Only used by Ford and now superseded however, still original fitment on many US manufactured Ford vehicles. The TPMS sits on the rim centre and is opposite the valve stem, held in place with a steel band.
Tire Pressure Sensor Manufacturers
In order to preserve the battery life the many sensors on a stationary vehicle revert to a reduced activity mode. To further preserve the battery life when stored as a replacement part the TPMS is put into a storage mode (in hibernation). The TPMS should also be put into this mode when the vehicle is being shipped from Asia or Europe (or awaiting shipment or distribution). Each manufacturer has a different way to bring the TPMS out of hibernation. In some cases the sensor has further different modes of operation that also have to be configured.
- TPMS sensors from Schrader Electronics are supplied as replacement parts in the off mode and are simply commissioned for vehicle use. An activation tool providing a 125 KHz transmission will initialize the TPM for vehicle use.
- TPMS sensors from Beru and Lear are supplied as replacement parts hibernated. Once pressurized over 25 PSI for a period of time they become operational.
- TPMS sensors from Siemens VDO (now Continental VDO) are supplied in a number of modes depending on the source of supplier. They can be supplied in TEST MODE and once installed on a vehicle will drive into the correct mode. Alternatively they can be supplied in SHIP MODE in which case they require activation by a 125 KHz modulated signal to put them into the correct mode.
- TPMS sensors from TRW are supplied as replacement parts in storage mode. To bring the sensor out of storage mode and to configure it for vehicle use requires a complex modulated 125 KHz signal. This usually requires a corporate tool as used by the vehicle manufacturer.
- TPMS sensors from Pacific are supplied hibernated and once pressurized and followed by pressure drop they become operational.
- TPMS sensors supplied to the aftermarket as Ford replacement parts are hibernated. Once pressurized over 25 PSI for a period of time they become operational. Ford have a number of suppliers such as Lear, Siemens VDO (now Continental VDO) and Schrader.
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