TPMS

[peter_rabbit]

Evening everyone. I recently just got a flat and had to change the tire.

Is there a way to reset the TPMS, it still shows around 9psi from the flat..?

Do it sound like the tpms in the spare is not working..?

Is there a tpms unit in the spare...?

I appreciate the responses in advance.

[TexasMadrone]

I also have a '03 M45. As I understand it when I bought mine, I was told that only the four "on the ground wheels" had TPMS. The system only can read four (and unfortunately doesn't say which location), and if you had a flat, only three would still be listing useful flat warnings. Mounting the spare would not change the listing back to four "on the ground Wheels", since no TPMS is in the spare now on the ground. It would still be reading the spare now in your trunk. Once you fix and reinstall the flat to "on the ground", you would be reading rolling wheels again. If you added a TPMS to the spare, the system would not know which was rolling or which was the spare! If anyone knows this to be incorrect, please chime in! You TPMS on the '03 M45 will reset once you inflat to over 27 PSI and it rolls for a few miles. At least mine does.

[SteveTheTech]

The spare might have a sensor, if it does it will have a metal valve stem.

The reason the display is not registering is that the sensors need to be programmed to the control unit. The only way to do this is at the dealer. They will have the tools to do the job correctly. There are products on the market you can buy but they do not activate the BCM and TPMS unit to reset the tire codes.