After Market Tire Pressure Monitors

[Curran]

I work for a company that specialises in setting up car plants to deal with tire pressure monitors sensors (TPMS).

The market is mainly the american market since they have recently passed laws stating that all new cars after I think 2007 have to have tire pressure monitors fitted ( eg 20K deaths a year due to car role overs due to partially deflated tires etc)

As a electronic engineer I am currently jumping through hoops designing a hand held tool to allow garages etc to deal with car fitted with these systems. From this work we are in a very good position to develope an in car aftermarket system using the main stream TPM Sensors.

Currently the main manufacturers of the tpms do not produce after market kits ( apparantly not enough it it for them) and the only ones I have seen are chinese kits where they use their own designed sensors etc and are supposidly not up to the job according to some automotive profesionals ( US, Korean and German) I have spoken to eg wrong pressures etc and can and do mechanically fail if the car does more than about 80mph

For the company I work for its a departure from what we normally do eg very high value systems but not huge numbers to low value items at huge numbers so there is a bit of internal discussion about it the effort is worth it etc.

Basically a system has 5 sensors and a reciever which is Battery powered and goes in the car cabin.

If the tire suffer a pressure or temperature change ( both up and down ) the TPMS start to alarm ( eg send out more messages) and the reciever in the cabin will displays information and more often or not tries to draw the drivers attention to the fact something may be wrong with the tyre by giving off an audiable warning.

Each sensor has a unique ID number so from this you can tell which wheel has the problem eg factory sets up the ECU in the US with the ID of the wheel on each corner ( it can make things interesting if you rotate the wheels as some cars need a trip to a suitable dealer to change the ECU settings others have a self learning capability)

you can also get other information from the sensor like gas temperature in the wheel/tyre assembly , if the wheel is moving and the direction ( only on certain types of TPMS) the Battery life the tpms has left.

I have 2 cars with low profile tyres eg the RX8 and a lexus is200 and as a result of nearly damaging a alloy on the lexus due to a nail in the tyre I will get my cars sorted with this kit if we go ahead and design it.

Would any one here be interested in this type of equipement ?

[Zee007]

What kind of cost would this device incur?

[Curran]

I am guessing it would be around £200

there would be 5 sensors supplied ( eg one for the spare) and a box slightly larger than big mobile phone.

the electronics in the "box" has the abiliy to be plugged into a USB port so if there was enough demand it could be made to data log etc.

To fit the kit it bascially requires the tyres moved from the alloy a sensor and value stem fitted into the alloy, the tyre put back on etc then balanced etc.

Some of these products just have a LED to indicate a problem eg low pressure etc but since we are currently working with a nice graphic mobile phone type of display showing individual wheels temperatures and pressures would not be a problem.