FWIW, on a 2008 if the TPMS lamp blinks initially for ~12 seconds before going solid it is a lost signal issue (interference) or another type of failure. Metallic window tint or an electrical device putting out excess RF noise are examples I've seen. If the lamp comes on solid initially, it senses low pressure in one of the four rolling tires. That's how to tell the diff between failure detection and low pressure.

The sensors can be a little off, and so can a tire pressure gauge, so err on the high side when airing up the tires for a test.

 

Outcome of blowing em up? Still have the alert light on?

 

Issue is resolved. I below up the tires to 40PSI and got no change in the light. So I finally broke down and took it to the dealer. At first they blamed the aftermarket remote starter, so I had to have the wires recut to stock set-up. Light still on, took it back to the dealer. It ended up being an improperly programmed WCN (wireless control node). This had been replaced fairly recently due to a no-start issue (it also interacts with the Sentry keys). But it is also the TPMS receiver. The dealer reports the light is out, I haven't picked it up yet, but I'm sure that's what it was.

Thanks all for the help, hopefully this thread helps some poor soul down the road!

 

thank you for following up! Most people just never circle back around. At least with resolution, this thread might help someone in the future.

 

No problem, it drives me crazy to see a dead-end post so just paying it forward!