walked out to find a flar rear tire in the morning......I thought the 2005 rx had the system to warn of loss of air? When changing the flat, noticied no tire pressure system on wheel?

 

i believe the 2005 still didnt have the direct tire pressure. i bet if you drove the car around the block the light would come on

this is because he old tire pressure monitor system only senses different rotational speed of the tire that is losing air via the abs system.

 

TPMS was launched in 2006 model year? Looks like it. If you do not have the TPMS valve, then you ain't got it.

 

You're right, 04 and 05's do not have that valve system. I'm grateful for that since my SC (which comes with the TPMS) has given me trouble at $210/tire when serviced at the dealer.