RAY: Yeah – by going back to the mechanic with a tin of warm brownies. That often gets us to try a little harder. That’s what your guy needs to do.
TOM: My guess would be that when he changed your tires, he accidentally damaged one of the tire-pressure sensors.
RAY: On the part of the valve stem that sits inside the tire is a pressure sensor with a little transmitter. That sends information about the tire’s pressure to the car’s computer.
TOM: The tire-pressure warning system on the ’06 Sienna does not tell you which tire is low, so you don’t know which of the two sensors got damaged.
RAY: But here’s what you can suggest to the mechanic. Tell him that while you’re not absolutely sure, it seems pretty likely that one of the tire-pressure sensors got damaged when he changed the tires.
TOM: Then make him a deal. Have him put new sensors in those two new tires. He can do them one at a time if he wants to. Maybe he’ll guess right the first time – he’s got a 50-50 shot – and he won’t have to do both.
RAY: And if a new pressure sensor – or pressure sensors – makes the light go off, then it was pretty obvious that he’s responsible, and you’re all set.
TOM: But if he changes both sensors and that doesn’t fix the problem, then you’ve determined that he’s not at fault – in which case, you’ll pay him for that extra work.
RAY: In that case, it may have just been a weird coincidence, and a sensor in another wheel just happened to fail after your tires were changed. But I doubt it. Good luck, Mir.
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