Quick question to confirm my findinga:
1. I start my RL and no lights come up... If I put MID on tire pressure monitor, rear left one does not show anything (see attachment).
2. After few miles of driving, TPMS system error light comes up on MID, showing code 38. At this moment all four tires on MID show nothing .. see attached pic...

Just confirming here: is rear left sensor the one to blame (and replace) or I am looking at replacing all four?

Car has 195k miles, prepping it up for another timing belt service this coming spring....

 

If they are original from factory, then replace them all. Or buy 4 and change the one in need and change others when you replace tires.

 

buy 4 new TPMS and replace them, I just replace all 4 of mine.

 

I'd replace them all at once.

 

Agree. If one has failed..the others are not too far from failing.

 

looks like they all have 200k miles life span, the A-spec wheesl I got from a 05 TL with 186k miles at the time of swapping and all sensor goes out one after another. I had enough after the 2nd one goes out and replace the rest.

 

UPDATE: I replaced one TPMS sensor (rear left) and the issue is now solved. I will wait for another set of tires, when these go on, will probably replace the other three.
Planning timing belt service soon, another chance to do it then too lol