My wife’s 2017 Edge is about to need tires. She has 86K miles on the car. The TPMS on my car, a 2011 Camaro, has just started to fail (left rear) after 13 years and 93K miles. I’ll probably ignore the Camaro until it needs tires, since we don’t drive that car much now. But should I preemptively replace the TPMS on the Edge?
My instinct would be “If it ain’t broke, don’t fix it”. Of course the day you come back home with new tires will be the day a TPMS fails. So you decide!
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I asked about replacing on my tpms, GM mechanic I know said don’t worry about it.
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We had a 2008 MKX (Edge twin) with original TPMS sensors that we sold after 15 years. Based on that, I’d pass. But much comes down to what your wife would like done.
Yeah I’ve brought that up several times when getting tires and the answer is just wait till they fail. I’ve had several fail and the cost is $80 each but the rest remain fine. I can’t tell for sure which tire anymore because of rotating, but I suspect a replacement failed early. So just replacing them may not mean trouble free for years like the originals. When the dashes show up, just be able to tell them which tire.
Does your state have state inspections? In some states if the TPMS light is on it won’t pass inspection.
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Before I had my Camaro inspected I checked, and in NC that will not fail inspection.
Its a great question. You’d think someone would have come up with a way to test the sensor’s battery. For example, compare the transmitted signal strength, when the battery is new, vs now. Of course you’d have to have a record of the signal strength when the car was new.
Maybe another reason for the manufacturer to provide a baseline sensor reading as part of the manufacturing process. OP, if the manufacturer had provided you the tpms signal strength info as part of the info that came w/your car new , would it be helpful to you now?
I don’t think so. I actually found a set of 4 on Amazon for $33. I think I’ll ask the tire place if they’ll install them for how much. I don’t need tires on the Camaro but if a second one fails (likely I think) I’ll do the same for that car and just pay for the tire unmount/mount.
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Ya want a baseline signal strength report on the tire monitors too? Like what the heck for? So in seven years you can check it again? If I were a dealer, I’m not sure I would sell you a car. Just too much future trouble.
Me : what is the battery strength on the tire monitors?
Salesperson: well to be honest the fords across the street have better batteries. I think that would be a better fit for you. Oh lunch time already? Gotta go, I’ll be back in an hour or so.
For assisting the car owner in this exact situation. Helpful data to help the car owner decide if they should replace the sensors as part of replacing the tires, or keep the existing sensors in service. Of course you are correct that the dealership would prefer you don’t do that, and just buy another new car … lol … maybe there’s no way the dealerships will ever allow this sort of data be provided to the car owners.
How will you measure the tire pressure sensor’s transmitter strength? Do you have equipment for this?
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My car comes with a signal strength meter. It lights up the TPMS warning when the signal gets too weak.
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I’m not suggesting I’d be the one doing that. Although I would for a high enough fee. It must be possible to get an estimate of rf signal strength without incurring too much cost. My $20 radio has a signal strength meter. @Texases makes a similar point above.
Not sure if you got my point. Nothing new needed, replace the TPMS sensors once the warning light goes on with the tires pressures checked as correct.
Depending on what TPMS tool the shop has, ask them to check the status of the sensor batteries. Even the ~$200 tool I have (Autel TS508) displays battery condition as either ‘OK’ or ‘Low’. Higher-end TPMS tools can give more specific battery status.
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Wouldn’t OP incur an add’l cost by that method, if the batteries were about to fail? Or are you saying it’s not a cost that’s enough to worry about?
Which is exactly what I am hoping to avoid by asking advice here.
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I guess it comes down to the question do the batteries fail based on mileage or time? If mileage comes into the equation the car will certainly cross the 93K boundary in less than a year. If it is just time, then they can wait for the next set of tires.
You’re assuming the RF signal strength actually diminishes in conjunction with battery depletion. Likely it does not appreciably change until the battery level is too low to power the IC used to generate the RF signal. Having messed with some proximity sensing circuits using RF, this is how I saw them function. They work until they don’t.
Regardless, the testing criteria would be very critical for assessing RF signal level. Precise location and distance, no interfering signals, an expensive tool that can discriminate only the sensor signal and be pretty darn precise to boot. And for what?
The onboard battery test is likely a single comparator input using a threshold detector. I haven’t seen a diagnostic tool that can extract anything more than Battery OK or Battery Low. To measure battery level would be much more sophisticated circuitry and not something the manufacturer would see value in providing. It’s not like you’re going to immediately crash and burn if the tire stops being monitored. The idea is, when the light illuminates, you take it in for repair at your earliest convenience.
If they’re 10 years old at the time you’re buying new tires, does it really matter if they are 60% versus 40%? Just change them if you’re risk averse. Otherwise, continue to wait for them to fail. It’s not like a huge extra labor cost to dismount, deflate and break the bead on a tire to replace the sensor…
One vehicle I have is 14 years old with the original sensors…
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