They are made from chocolate!
It’s a problem with the whole Chrysler range fitted with a TMPS (Tyre Pressure Monitoring System). The problem is that the valve stem corrodes and it becomes easy to snap them off when checking or adding air, resulting in an instant flat tyre.
New rubber stemed sensors are available at a similar cost to the old style transmitter and valve
Here are a few tips you can try to reduce the corrosion of the stem
1. Use stainless steel or chromed valve inserts, this will stop the internal corrosion of the stem due to non compatible metals
2, Use a plastic or better still a genuine Schrader dust cap. This will keep the road salt out etc Do not use metal aftermarket dust caps. these have been know to weld themselves to the stem (If you must use them,apply grease to the caps before fitting)
3. Keep the valve stems clean and use car wax on them in the summer and WD40 in the winter to keep the salt out.
If you do happen to snap your stem, either completely or just partly. you can have the valve replaced with a standard rubber one as a temporary measure as they will fit, but you will have to get it replaced or repaired, as you are unable to turn the warning system off and the warning bong, warning light and message will appear on the dash.
(TPMS (Tyre Pressure Monitoring System) will also become part of the MOT in 2013, but it appears this will only be an "advisory" on cars registered before 2013 )
Spare parts are available to repair these valves, so all is not lost.
I now carry these in stock and can supply them, or send you links as to where you can get them
If you have the valve replaced by a dealer, do NOT accept a charge for resetting the system to read the new sensor, they re-set themselves as you drive off! (mine re-set before I even backed out off the drive).
Watch the price you are charged too ( they are available on Ebay, both new and secondhand)
Note: I use two old wheels and tyres for drag racing, both are fitted with standard rubber valves. I neither get an alarm or message up on the dash? Can anyone tell me why?
Steel valve inserts are better than brass
They are standard in the valves but they may have been replaced when a tyre has been in for repair or replacement
Genuine schrader dust caps, again standard to the valve but they may have been replaced, either at a tyre bay or by the owner
Spare parts are available.
The bottom three parts should be replaced every time the valve is removed from the rim.
New stems can be bought separately or part as a kit