I look at my tires whenever I approach the vehicle, and check the pressure every week or so. But, I wouldn't say the TPMS is worthless. Let's say I check the tires before a long trip. They are OK. Then, a couple hours into the trip, a tire gets a nail in it and starts a slow leak. When it gets down to 29 psi, the warning light will come on and chime. At that point, it doesn't matter that it doesn't tell me which tire. I'm just glad to know a tire is leaking and I can get off the highway before it gets low enough to let go all at once.

 

I feel you're kind of reaching for a use case for that TPS idiot light with that one. My counter point would be as such. If it's really that much of a slow leak, you're eventually going to feel the air getting lower in the tire either by the steering starting to pull to one side or a rougher ride when hitting bumps in the road during your trip. If it's really that long of a trip, we all tend to stop via a rest area, gas station, or restaurant as we're traveling so there's typically plenty of opportunities even on a long trip to visually inspect and notice if your tire pressure is getting low or not.

I understand some feel they're a useful feature. Personally, I find them to be more of an annoyance than a feature since I've found myself in more than one vehicle trying to trouble shoot them more often than they've alerted me to a potential problem. I drove in a Toyota Sienna company vehicle. The idiot light stayed on for at least 7 years in that vehicle. The tire pressure was fine, myself and at least 50 other employees who drove that vehicle didn't know how to turn that chime/light off, and no one cared to trouble shoot it to find out. So I dunno, but when a supposed feature spends more time annoying you than it does helping you and that help is minimal, I call that a worthless feature.

What makes them a further annoyance is that they're not even a real-time monitoring system unless you're driving. My wife has a Renegade which has the 4 tire display monitoring. Every winter the pressure drops in the tires due to the colder temps, she gets alerted her tire pressure is low. I go out inflate her tires, check the pressure with a gauge. Tell her she's all set. She starts it....tells me, "it still shows it's low" and I have to tell her to go drive it so the dumb system has time to realize I inflated the tires.

 

If I had an early model that didn't show each tire's pressure on the display, I'd be completely aggravated and turn that crap off. Completely worthless. The newer ones that display each pressure are marginally better, but still is what it is. I use mine airing up/down for wheelin trips to generally hit my target, but I agree many people don't find them useful. There was one wheeling trip hours from home that I could see pressure dropping slowly on the ride home, pinpointing a small leak at the bead. I had to stop along the way and air back up, and will say it was nice to know in advance than the next morning when I unexpectedly walked out to a completely flat tire. With one of mine out, I'm on the fence about paying anything to replace it. Odds are likely I replace and just have another one of my 5-year old sensors die, and I'm not willing to go down the path of spending several hundreds to have those dumb things replaced. More likely I just disable to feature like the majority of others.

 

I'm only familiar with the early ones that don't indicate to the driver which tire is low, which can be a pain (you know where). They are susceptible to RF interference from things like poorly designed electronics, often inside stuff that plugs in the lighter or OBD connector from my experience. If the TPMS light blinks for about 75 seconds then goes on steady, there's a system fault such as RF interference or failure of a component -- Not a low tire. The lamp goes on steady immediately to indicate a low tire. In either case there's a chime.

If the TPMS light blinks, chimes, goes out, then blinks and chimes again, and repeats intermittently (or incessantly), it's an intermittent failure like RF interference, bad sensor, etc. If I'm remembering correctly, a complete failure just chimes once, and a low tire just chimes once.

The factory spare has a sensor already in it that won't alarm until it rotates, and it takes several miles to learn that there's new sensor rolling and clear the TPMS lamp when rotating/changing tires.

My son had TPMS light up on a busy highway. I figure his wife made him pull over immediately, near an off-ramp. He said by the time he got out to look, a tire with a drill bit in it was almost flat. He almost certainly would have been fine without TPMS, just like with old cars, but it was nice that it worked like it should and didn't even scratch the rim. Similar happened to me in the JK, but driving slower near some new home construction.



Some additional info on RF interference: I solved one TPMS RF inference problem by adding a clamp-on ferrite core on the cable nearest the device. Suspect the cable was acting like an antenna for a broad spectrum of RF noise. Long term, the best solution is getting rid of junk that emits too much RF noise.