OT tire pressure warning light

Learned something today! The tire pressure warning light in my truck (Rav4) came on and all the pressures in the four tires were fine! Drove me nuts, then I found out the spare tire could be low. It was! Light went out.

Thanks Andy, that’s good to know. I had
a V WW with a computer. It checked everything except the battery fluid level. It used the air pressure in the spare tire to run the windshield washers.

Thanks, I did not know that
Your Rav4 may be fancier than mine, but I will have to see if the light may be pointing me at the spare. I always carry a gauge to check if that light goes on, and yeah that would make me nuts too.

Watch for a false tire pressure alarm near an airport. The radar or glide slope or whatever can screw things up temporarily.

Also the sensor in the tire can go bad
Had that happen on 2 different vehicles.

My wife picked up screws on
the sidewalls of both front tires.Didn’t need the gage.

Yes, as I learned

– Last Updated: Oct-27-16 1:31 PM EST –

on Saturday when I pulled my car (2016 Honda Fit) out of the garage to install my Hullavator cradles. Right front passenger tire was flat.

A 45 minute wait for road service, then a drive on the donut to the only tire repair place open. Three hours later the tire guy tells me the tire is fine - the TPMS valve stem was dislodged. Hadn't run over anything; car sat inside the garage all night.

That made me grumpy as it ruined my paddling plans.

Do not like those gizmos. I'd rather rely on me and my tire pressure gauge.

standard off road

– Last Updated: Oct-27-16 4:24 PM EST –

equipment includes an electric air pumpwith electric extension spliced in or cans of compressed air...pro level tire repair kit (see amazon)
diagonal wire cutting pliers and small vise grips...rubber work gloves(Performance from Walmart)...a small bottle of water n dilute dishwashing liquid( finding leaks)..paper towel roll..
and the deluxe box includes a battery drill with bits just larger than the plug diameter ( matched to your tire type) with ! a socket adapter and socket(s) for the lug nut ....a 2' breaker bar with 1" extension n coupler to match sockets...a sharpie for marking 1-2-3-4-5-6-7-8...a can of CRC silicone lubing the nut extraction....a wire rotary brush for cleaning the lug bolts off with the drill...a bottle of Locktite blue for reassembling the nuts ( no corrosion no loosening)
and a 5/8ths plywood or 2x platform for the jack abt a foot long n 6" wide and and wooden blocks ensuring the jack is always at an optimum height even if the tire is dead flat.

and a visible orange blaze 'vehicle off road' indicator. a dayglow mesh vest from Home Depot for yourself.

and remeber ! shuttle vehicles traveling on high crown roads should use staggered tire pressures with right side higher than left, rears higher than fronts for RWD and the difference front n rear less on the berm side than the road side, for RWD.

I have forgotten FWD specs.

using a mid range battery drill, mine's a Porter Cable from HD requires a less than full setting and a loose nut via the breaker bar with the CRC n clean threads

still using clean threads preventing bolt damage I now have a mid range battery Sears impact drill for lug nuts. Beastly.

Bolt threads are often damaged. Buy a small triangular file at HD, buy 3...mine disappear like Cliff bars. A die came from Amazon at an incroyably ridiculous price but that's not the Ford thread percentage n the die is use able only for the first 2-3 threads. Thus the lugs go on a lot easier than before when the 1-2-3 threads were at prob 80%.

I wipe the CRC off with isopropyl ( flea killer) but keep a can in for hinges, rubber door seals, locks, key slots...wiping it off can wait until you get home.

My on the road opinion on stagger is stagger is essential n if not equipped then your rig isnot up to speed.

For the Florida group, the trip across the St Johns on 40 from Ocala to Daytonah is difficult without the stagger. With stagger, the van's right tires go right against the dots or if necessary eyeyehhahhhahha across dots onto the berm. Completely stable with stagger drive on no problem no continuous correction necessary juggling the beast down the road.


– Last Updated: Oct-27-16 3:35 PM EST –

I don't like the gizmos either. They should start with making an aluminum wheel that won't leak. Then make a tire that can fill and maintain it's own pressure, and get rid of the damn gizmos.

You don’t have to live with them
They’re a pain in the a$$, as they can lose their connection with the TPMS computer due to RFI or EMI and it costs a ridiculous amount to have the dealer reset them, just to turn off the idiot light. Like many of you, I never wanted them in the first place and have no need for them.

The law requires that dealers and repair shops install TPMS sensors in wheels that they INSTALL on cars that are TPMS equipped. However, there is no law against buying wheels and tires without them and installing them on your car yourself. When I bought snow tires and steel wheels for my car, I told the tire dealer that I didn’t want the sensors and would install them myself. That was all that was required.

I don’t know what the requirements are in other states, but here in NH there is no requirement that the TPMS is working in order to get the car inspected or registered. You don’t have to waste your money on fixing this junk.

Obviously, this won’t work for everyone, but it’s an option for some. I long ago learned to ignore the TPMS light and don’t even notice it now.

That’s interesting.
Found this when I started looking into Michigan law:

“a motor vehicle repair business would not be violating 49 USC 30122(b) by removing an inoperative or damaged TPMS sensor and replacing it with a standard snap-in rubber valve stem…However, a motor vehicle repair business that goes on to make any other element of the TPMS system inoperative, for example, by disabling the malfunction indicator lamp, would violate the ‘make in­operative’ provision.”

In other words, when mine fail (and they will), my auto tech can replace it with a standard valve stem.

The TPMS in the wheel has a battery that supposedly will last 10 years. My Rav4 is a 2009 and still runs like new. I still bring it to the dealer, free oil changes! Their mechanics are good and know the vehicles. They have kept my RAV4 running great. Warning lights drive me nuts, and prefer getting rid of them.

Here’s what I want to know:
If this technology can measure tire pressure as accurately as what seems to the the case, why can’t they apply that to tire-pressure gauges? In my whole life, I’ve never seen two tire-pressure gauges that will agree with each other when used to measure the exact same pressure (4 to 6 pounds of discrepancy from one gauge to the next seems to be normal). Now, I’ve never compared two digital gauges that way, but I’ve also never had one of that type which lasted long enough to compare to the next one that I buy (I had one that lasted a year, and a few since then, each of which malfunctioned within a month), so if they could even make an electronic gauge last as long as the telemetry devices on modern cars, that would be something. Anyway, I have one pressure gauge with a dial that I think is pretty close to correct (I have three others that aren’t even close, and three “push-stick” gauges that aren’t even close), and that’s the only gauge I use.

Same issues with them.
Then I found this one:


Hoping it lasts longer than the others that have gone by the wayside.

TPMS sensors aren’t that accurate

– Last Updated: Oct-27-16 9:22 PM EST –

double post

TPMS sensors aren’t that accurate

– Last Updated: Oct-27-16 9:27 PM EST –

They only indicate that your tire pressure has dropped below their preset limit, but you'd never know if that is exact or not because it really doesn't matter.

As for gauges, you can get very accurate analog and digital versions, but you have to spend a bit on them. Again, absolute accuracy of a gauge is not that important, what matters most is that it's repeatable. I always determine the optimum pressure based on how the car rides and handles, and how the tires wear. Once I figure that out, I just use the same gauge to check and adjust them every time. I've had the same gauge for over 20 years, so I'm very familiar with it.

Just for the heck of it, I checked and adjusted the pressure in my spare tire, though I'm not sure if it has a TPMS sensor. It will be interesting to see if that shuts off the light. I'll kick myself for not thinking of it if it works.

Mine came on
Sunday running shuttle on the Manistee. Tire gauge as in the wife’s car so I eyeballed the tires & they looked fine. Drove home and finally checked on Tuesday. They were all a little low and one maybe a little more. Filled them up and all is good. It won’t matter much soon as the Blizaks should go on in a couple of weeks. They are on steel wheels & I probably won’t spend the time & money to get them reset unless I happen to get up to Subaru for some other reason.

No problem with familiarity

– Last Updated: Oct-27-16 10:29 PM EST –

Okay, I'd been lead to believe the pressure sensors on car wheels were more sensitive than that. Heck, if that's all they do, they're just a very expensive substitute for a person's own eyes.

As far as gauges and tires, have no problem with familiarity, though I honestly can't imagine testing different pressures to see how they affect wear (for most people's driving habits it would take more than a year for any new wear pattern to become visible) and I don't drive aggressively enough to notice much in regard to handling (which is why my tires last so long, 135,000 miles per set, lately), though I can feel differences via the bumps in the road. I just figure that if a decent gauge costs 20 bucks or more, it ought to agree with some other supposedly-decent gauge rather than test my memory about whether this is the one that reads 6 pounds low or the one that reads 4 pounds high. You are right about precision being more important than accuracy, but I'd rather not have to worry about either, since there's really no excuse for that.

Good Info…
I don’t have the gizmos but if I diagnose someone else’s problem I’ll look like a genius…

See here

– Last Updated: Oct-28-16 2:40 AM EST –



I have a digital as a freebie a PITA at contact with tire valve

Positive wudbe a snack screw on then press button for reading. I doahn no what $$ level this is but track gauges are $$$.

The battery impact wrench is available with torque settings for screwing back down as final tighten.

Metal lever lock hose ends are super on pumps. Rare. I looked to buy a couple from Loose Screws but LS was sold out...10 years ago.