I asked this question a few weeks ago about tire pressure sending units
 

and got an answer which I appreciate. But it turns out not to be the case. I asked if the pressure sending unit would know it was on another corner if I rotated tires. I was told it woould. Well, my info center tells me the passenger rear tire is running slack. When I check them, it's the front tire. When I fill it, the light & message go away. How do I fix that? Thanks.

It doesn't matter where the tires are located. They read off of the car location so rotation doesn't matter. If it's giving you false information there could be a problem somewhere else. Personally I always saw those as a useless invention created to break and sell parts. It really isn't that hard to check the tires every week.

I'm stumped then. All I can tell is that the offending tire is on the front & the info center tells me it's on the back. The light for the rear tire goes out when I add air to the front tire. If it was a faulty signal, I'd have exploded that tire by now. I'm almost due a set of tires, so I'll ask the shop about it when I get them. Thanks.

What does your owner's manual say about "relearning" the tire positions? Don't you have to put it into relearn mode, let some air out of the LF until horn blows, add air, then do the same thing on the RF, RR, and LR?

I've never done this since my 2003 does not have the feature and my Buick uses the ABS system with no sensors in the wheels (seems to me to be a better way...I smell the gubbermint making more rules here!) Anyway, it is my understanding that if you rotate tires the system has to relearn where the sensors went.

OK, here's the part where I shamefully admit that I haven't looked for it in the manual. Mostly because the manual is geared towardletting the service dept. do everything for you. All you need to do is drive it & take it in for service.

Well, take a look. You may find it's not as bad as you think. You can pull up an online owner's manual on gmownercenter.yahoo.com.

Here is a thread dealing with TPMS: Tpms Reset - GM-Trucks.com

Gerald