???
Top is white/w green
bottom is green

 

I think I found the problem. Initially I had removed the headlight but could not see the initiator wires. The problem was while I knew the colors of the wires, I did not know their gauge.

To “get eyes on the wires”, I removed the wheel arch guard, found the initiator identified the wire thickness, and the direction the wires ran.




The wires are taped but have no plastic guard like in Cee Jay’s photo. I traced them up to the top of the bumper and saw they are secured to the chassis with pushpin zip ties. The problem from there was to determine if there was a break in the wires anywhere.

I needed to start at the bottom and trace up to the top. I, therefore, lifted the car up and dropped the splash guard to unwind the wires and really be able to look at them.




I didn’t find an issue at the bottom, but at the top I DID see an issue.

take a look at the photo below. You can see an abrasion in the white/green wire. The copper in the green wire was also exposed.




I think they were touching just barely once every few hundred miles. This would explain why the Tpms fault would be triggered but then immediately disappear.

Incidentally, it looks like the issue was just at the zip tie pin securing the cable to the bumper up top. I taped the wires very well and resecured them.

I hope this was the only issue. It’s possible there could be abrasions elsewhere but I’d be surprised. It’s not likely (though not impossible) to have multiple abrasions in one circuit.

I’ll have to drive it for a bit and see if the issue recurs.

Thanks again for everyone’s help!!

 

FYI this is what I use to read all of my TPMS pressures. It reads pressure , temperature and battery life. Also measures key fob functions. And if you buy their sensors you can clone your old sensor and install them. Sensor costs between $30-$50. You can also change the locations of the sensors in the TCM.

 

Visting the site for old times' sake. Thought I'd throw a contrary opinion based on my experience.
Mine was a 2010, in-service date was 0ct 2009. This happened in early 2020, so those sensors were about 11 years old.
Had the "christmas tree" of blinking (and changing) yellow warning lights about Tyre Pressure Low.
Tried the over-inflate, tried swapping the sensors around, the whole deal. All the fixes worked for a week or so, then back to the lights.
Dealership thought it might be a module issue. I paid them $100 to "reflash" the module in question.
Problem solved. Never came back. Never replaced any of the TPMS sensors, and had the car til about three months ago.
For what that's worth...