[s-cars] TPMS

[Franco Barber]

The Hella unit allows for an extra sensor that is in a spare tire, and
gives you a way of swapping the position of the spare tire and one of
your tires, but as you said there is no way to have an extra four
sensors associated and swap them in wholesale for the four sensors in
use.

Instead, what you would have to do to change from summer tires to
winter tires is to follow the same procedure that you have to use each
time you rotate the tires: reprogram the four tires one corner at a
time.  This is done by putting the receiver into a programming mode
and then deflating each corner in turn by at least 3psi -- the
receiver learns the ID of each corner's sensors this way.  I don't
have the four extra sensors to try it, but from my reading of the
manual using this procedure you would introduce four entirely new
sensors each time you swap out summer for winter tires or v.v..

The other two sensors that the Hella unit can monitor are for pickup
trucks with four tires on the rear axle.
They wouldn't be useful at all for winter tires, even if you chose to
forego having a sensor on all four winter tires.
If you tried to use them that way, the receiver would complain about 3
missing tires all summer long, and 4 missing tires all winter long.


Regarding sensor damage on tire mounting:  when I had mine mounted, I
brought along a print out of Hella's mounting instructions, and it's a
good thing I did.  The tech at the shop I used told me that they had
been trained on installing this kind of valve-stem mounted sensor, but
that the method that their training said to use would not have worked
at all for my sensors, wheels (16" avus), and tires (pirelli). He said
that method would have damaged the sensors, but the method in the
Hella instructions worked fine.  So I do suggest printing out the
instructions and handing them over to your installer and having an
explicit discussion about the installation method to use.


Franco

On Thu, May 29, 2008 at 12:06 PM, Douglas Landaeta <dlandaeta at gmail.com> wrote:
> Hmmm, Hella system monitors up to seven tires - a bit shy of both Winter and
> Summer sets - presumable you could reprogram - but the odd thing is that the
> 'extra' sensors cannot replace the original sensors. Also, watch out for the
> tire rookie that may damage these things on any mounting / dismounting. I've
> been waiting for an elegant solution such as this, but am still a bit
> concerned... it certainly seems better than those units that strap around
> the inside of the wheel.
>
>



-- 
Franco Barber
feb at febsun.cmhnet.org