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TPMS problem

I have a 2015 Rav 4 and 2016 Optima. 1st cars with TPMS in tires. My rav 4 goes low and I pump up and the light goes off. The same happened with the Optima and I pumped to 36 and they read from 31 to 36. I’m not too worried as I know the tires are at the desired pressure but I researched the TPMS and see that the battery is only good for 5 to 10 years with 7 average. I guess that when tires are needing to be changed, you have to start buying TPMS units to replace the old ones. They’re not cheap either (42 for optima each). And I just changed all 4 tires on my rav and they won’t need new ones for 2-4 years. I guess I could buy new ones and get all tires removed and rebalanced but you’re talking 150 to 200 for sensors (4) and mounting/rebalance of about 100 per car. What I’m not sure is once all 4 batteries die, does the dash have the warning light on or off due to no signal sent??? if so (off), then I can just check tires every 2 weeks and get sensors when tires are needed. Any help/comments??? thanks.

You will get an indication of TPMS failure when or more batteries in the sensors go dead, usually the TPMS light flashing or a message in the message area, if so equipped. You can just check the tires yourself until the sensors are replaced. Of course, the constant nagging message can be annoying. The batteries in some sensors can be replaced, I believe.

thanks. I saw some said you can cut the plastic where the battery is but not sure if discount tire would do that. Sounds messy. If the light doesn’t stay on the dash, I can pump tires. Been doing it since 1977 so it’s nice for the sensors but when they go, I can’t change them myself. Now the next question is will they charge to replace them but what choice do I have. Thanks again. Good day.

When ONE dies, that light will stay on forever. Same for 2, 3, 4 or even 5, if the spare has one. Some cars will tell you a battery is bad and which one it is providing its been told the tire’s position after rotation.

You absolutely can ignore the light (or tape over it) and just check manually. Maybe some states would fail the car for that in an inspection, I don’t know.

I’ve not seen any TPMS sensors that had a replaceable battery. I would not trust one I cracked open to install a new battery and you’ll never get a tire place to do that.

+1
I will add that, if the OP is a Costco member, their tire center will replace the TPMS units for far less than an indy tire shop would charge.

makes sense that the light stays on if one goes. Like you said, the others are okay and can read pressure but you have to look at that light. And I agree that an auto place wouldn’t break open a sensor and replace it. so it sounds like you have to either just do all 4 when 5 years or 7 years comes up or do when tires are changed and buy the sensors and be ready. Technology is great but not when I can’t do it myself. Look at cell phones, the old galaxy samsung had replaceable batteries. now you have to either buy a new phone or take them in as it’s way complicated than removing a cover and replacing a battery.

Apple’s iPhone pioneered that… they sacrificed replaceability for a little extra battery size in their iPhones and iPads. The batteries have gotten much better, though.

Lots of products are designed not to be serviceable mostly for lower cost of assembly. A spot weld, glue or plastic heat weld are cheaper than screw bosses and screws.

That is up to the shop. They might not charge for installing if they also sell the tires . They may have a lower price but charge for labor . So the answer is who knows other than the shop .

my wife just drove the car and said the lights are on the dash (tire indicator and triangle) but one tire is blinking in the quad display showing pressure. all say 32 or 31 even thought I pumped to 36. so that one tire must be dead. oh well, I said get used to seeing the lights for a while.

Why 36 lbs ? Why not go by the door plaque that lists the correct pressure ?

Your tire pressure gauge is off, the tire pressure sensors are more accurate than most gauges.

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I’ll have to look at the manual but I always do my tires to 34-36 and no issues with the light. It got down to 19 degrees Christmas morning and the tire pressure dropped and the light went on. I have to use another gauge (pencil vs. the more expensive round one to compare and see if my gauge is bad but I doubt it). You and nevada are right. I pumped about 15 times when usually it takes like 25 pumps of the floor pump/bicycle pump to get the tires to go from around 28/29 to 34 plus so I’ll go check them again today. Thanks for the help. Now I know when one is bad and what to do. It’s only money right!!!

The tire pressure numbers are on your drivers door jamb .

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yeah, pencil gauges are not perfect and it might be time to get a new dial type as it’s probably 15 years old.

yes. I just looked. says 34. so if my gauge was correct, I’d be okay at 35/36 so it must be off. I’ve worked on cars for 43 years but these two cars are the 1st with the TPMS on it. So I’m learning about that. I’ll get a new gauge too. Don’t want to pump them over 40’s and have wife blowout and flip.

my pencil gauge said 31ish. Accu Gauge dial says 35/36. I did 10 more pumps and pencil shows 35 and accu gauge 38 now. Those lights should go off. Now the question is what gauge is right. Don’t like 38. Might buy a new one or go to discount tire to check theirs vs. my dial gauge.

The display on the dash is right. I find that less than 1 sensor out of 100 is off by 1 PSI. You can index your cheap gauges off of the tire pressure monitor display.

yeah, I’d think the accu gauge is better than a pencil but it can be old/off. Time for a new one. I see there are ANSI certified gauges. I’m a scientist so I understand accuracy/precision issues. I can go to Discount tire to compare to theirs or just get a new one. thanks again.

as a last post as you guys have better things to do, I started the optima. no lights. Dial Gauge says 37 now. My rav which is 33 on the door, is 34.5 with the dial gauge. So I don’t think my gauge is off that much unless the ravs are set to say 30 even though the recommend pressure is 33. The kia might be set at 34. Thanks again. I learned some stuff about TPMS and gauges.

On my GM if the sensor goes out, I just get a reading of “—” for that tire and the rest read the pressure normally. In ten years though I’ve only had one go out. $80 at the shop. I considered changing them with the tires but the shop said just wait until they go out. So far they are correct. As they say, your results may vary.