Thread: Tpms,....wft?!?!

Ok so I have an 04 GTP and have had my tire pressure light come on before. Found the low tire and repaired accordingly, no problem. I have worked in a chevy garage before and have delt with the sensors before (band and valvestem type). While replacing two tires I discovered to my confusion, no tire pressure sensors!!!!! How the hell can this be? How can the car know when the tire pressure is low if there aren't sensors? I am very confused by this. I guess I should have known something was screwy when I put my winter wheels (monte wheels) on, the system didn't give me any trouble and I didn't have to do any reprogramming to reconize the different wheels. And the light came on when I had a low tire too!! I've been baffled by this and Hopefully somebody can shed some light on the situation for me. Thanks!!!

any body? The light went on again yesterday and one of my tires was 12 lbs low (damn nail) so obviously it's responding correctly but I just don't know how in the hell it knows.

hi, what happens is that it sens the rev's per min of the tire and check for changes in a different tire which throws the light. it compare the different rev/min tire with the rest of the tires to check the difference. it only throws the light if there is a huge difference between tires. this might be not the best description but hopefully you get the idea.

cheers

oh another quick note that they changed this on 07 onwards pontiac grand prix to tpms sensors in the tires.

Thanks for the response. I've never seen it like that before. I worked in a chevy garage from 04 to 07 and all the vehicles that had the system had monitors in the wheel by valve stem or strap clamp on the wheel. Thanks again.