Team - On cold mornings, my TPM light comes on eventhough the tire pressure is OK. If I follow the OM and reset the TPM system, the light goes out as it is supposed to.

Any ideas on why the system seems to only do this on cold mornings (50 F - in central Florida)?

Thanks - Al

 

@ 50 being cold

give your dealer a call

 

I do not think the pressure is OK! TPMS is mandated by law on all vehicles except for the heavy trucks sold in the US starting in 2007. The law requires that the system warn the driver when the pressure drops by 25% of the correct value (check the sticker on the B pillar). The pressure will be reduced by approximately 1 psi for 10F drop in temperature...check the pressure when the tire is cold and add air to bring the pressure up to max and the problem will go away.

 

When it gets "cold" here, or better yet, last year when we were in Jacksonville in February we had that issue with the BMW. Also showed our coolant level as being low... but it wasn't. After a little warm up everything was fine. Doesn't re-setting set the pressure indicator to that new lower level?