Check Your Spare Tire Pressure

One thing I was disappointed about was the CX-5 not having a page on the instrument cluster showing individual tire pressures [each as a figure in psi]. Was useful when I had a slow flat on a rental car as could see the figure descending until it got to ~22/23 psi and then the warning coming on [showing the correct tire that was low]. May also be useful to easily see when a tire is down a few psi to prompt further investigation.

Though I don't think the rental showed the psi on the spare.
Not all TPM systems have individual pressure monitors in each wheel. If you don't have this you don't get a readout for each tire/wheel.

There are two types of TPM systems. The above and the type that uses the vehicles ABS system to determine if a tire has low pressure, as compared to the other tires in the system. The ABS type only knows if a tire is low by comparing the speed at which it rotates (an underinflated tire is smaller in diameter than properly inflated tire and therefor rotates faster) to the other tires and if one tire is rotating at a different rate than the others it sets an error code and this gets displayed. The system doesn't tell you which tire is low only that one, or more, is.
 
The 2019+ Mazda 3/CX30 have individual tire pressures. It will make it to the rest of the line as the models get their redesigns.
 
Not all TPM systems have individual pressure monitors in each wheel. If you don't have this you don't get a readout for each tire/wheel.

There are two types of TPM systems. The above and the type that uses the vehicles ABS system to determine if a tire has low pressure, as compared to the other tires in the system. The ABS type only knows if a tire is low by comparing the speed at which it rotates (an underinflated tire is smaller in diameter than properly inflated tire and therefor rotates faster) to the other tires and if one tire is rotating at a different rate than the others it sets an error code and this gets displayed. The system doesn't tell you which tire is low only that one, or more, is.
Interesting, thou the ABS method doesn't seem that good e.g. if all tires are going flat [& won't know at engine start until you move]
The manual for my CX-5 2021 says [page 4.255 - over 3 pages long on TPMS]
"The tire pressure sensors installed on each wheel send tire pressure data by radio signal to the receiver unit in the vehicle"
This indicates the TPMS sensor is on the 'wheel' and not the tire - I thought the sensor is in the stem of each tire valve?
 
Uh, the stem/sensor is bolted to the wheel, not the tire. What’s the problem?

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Interesting, thou the ABS method doesn't seem that good e.g. if all tires are going flat [& won't know at engine start until you move]
Yes using the ABS sensors for TPMS does have drawbacks like you said, but the big advantage is the lower cost by utilizing existing sensors. And all gen-1 CX-5’s use this ABS sensor TPMS.

The manual for my CX-5 2021 says [page 4.255 - over 3 pages long on TPMS]
"The tire pressure sensors installed on each wheel send tire pressure data by radio signal to the receiver unit in the vehicle"
This indicates the TPMS sensor is on the 'wheel' and not the tire - I thought the sensor is in the stem of each tire valve?
The dedicated tire pressure and temperature sensor used in all gen-2 CX-5’s is a part of valve stem like CarpeDiem stated. But the complaint here is Mazda has wasted the function of dedicated and expensive TMPS sensors and doesn’t provide more information available from the sensor. A direct read tire pressure display on each tire is easy to implement with those dedicated TPMS sensors which will be much helpful to the car owners such as the one found on the Nissan Rogue:

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Interesting, thou the ABS method doesn't seem that good e.g. if all tires are going flat [& won't know at engine start until you move]
The manual for my CX-5 2021 says [page 4.255 - over 3 pages long on TPMS]
"The tire pressure sensors installed on each wheel send tire pressure data by radio signal to the receiver unit in the vehicle"
This indicates the TPMS sensor is on the 'wheel' and not the tire - I thought the sensor is in the stem of each tire valve?

What CarpeDiem said above. That's for systems with individual monitors in each wheel. These systems are superior in that they show what's going on with each wheel/tire combo.

This system mentioned above does have it's drawbacks as compared to the ABS based system. The first being those monitors take batteries. Batteries that will need to be replaced at some point. Some of these monitors are designed so that the batteries can be replaced, with the tires off of course. Others don't have conveniently replicable batteries and the entire sensor has to be replaced. Which means that the sensor will have to be 'mated' with the car's system. Might need the dealer for this and it certainly won't be free.

The other issue with the in wheel/tire sensors is when it's time for new tires and if you're unlucky enough to get a knucklehead working on your car who isn't paying attention to (or doesn't know) what he's doing. The knucklehead breaks your sensor(s) while removing/installing your tires and then what? Most likely the knucklehead isn't going to fess up when he makes this mistake and you won't know that he screwed the pooch until you take your car home and get an error from the system on the way.
 
The Mazda 3/CX-30 show individual tire pressure. It will be coming to the rest of the line soon
This’s a page of owner’s manual from 2020 Mazda CX-30. If the future CX-5 is going to feature a direct read tire pressure display it should be similar. This direct read tire pressure display is long overdue for CX-5 with introduction to new TPMS since 2017 MY. Just hope the display has recommended tire pressure and is as colorful as Nissan’s.

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Just to clarify a few things....

TPMS sensors in the wheel are typically on the inside of the wheel but integral with the valve stem. They have non-replaceable lithium batteries which should last 5-10 years. For most, they should last between tire changes and tire shops will always recommend they be replaced with new tires. I recall the cost of the sensors (with built in batteries) was about $10 each. There is a reset procedure to pair them with the car but tire shops have all the equipment needed... you don’t have to go to the dealer. Ham-fisted tire techs do occasionally break one when dismounting a tire (I.e., to fix a puncture) but shouldn’t if they have an up-to-date tire machine and proper technique. Go to one of the major chains like Discount Tire and you should be fine.

I’m also disappointed that there is no direct readout of tire pressure on my 2021, either on the dash or with the MyMazda app. It’s a chintzy omission.

- Mark
 
TPMS sensors in the wheel are typically on the inside of the wheel but integral with the valve stem. ⋯ I recall the cost of the sensors (with built in batteries) was about $10 each.
TPMS sensor is much more expensive than $10. OEM TPMS sensor, part no. BHA4-37-140A, is $101.03 MSRP each. Most popular aftermarket sensor, Autel MX-Sensor 2 in 1 (315MHz + 433MHz) clamp-in TPMS programmable sensor is about $30 each. If you want new TPMS sensors during the tire change at Discount Tire Store, it’s about $60 each for BH SENS TPMS sensor.

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$10 usually is for a standard rubber valve stem, or a “rebuild kit” from Discount Tire which includes the rubber grommet, retaining nut, core and cap.

Finally there’re many different types of TPMS sensors. Make sure to get a TMPS sensor which is Mazda compatible, or pre-programmed to be Mazda compatible.
 
Just hope the display is as colorful as Nissan’s.
View attachment 298136

Seeing the above ajar [top left] text from Nissan manual reminded me of another similarish lack-of-specificity on the CX-5 - it doesn't show which door is not properly closed when the red light comes on [again, presumably the system 'knows' which door(s) triggered the warning]

Where CX-5 does get it right, it clearly shows [with individual red/green icon] who hasn't got their seatbelt on [including the back middle]
 
Seeing the above ajar [top left] text from Nissan manual reminded me of another similarish lack-of-specificity on the CX-5 - it doesn't show which door is not properly closed when the red light comes on [again, presumably the system 'knows' which door(s) triggered the warning]

Where CX-5 does get it right, it clearly shows [with individual red/green icon] who hasn't got their seatbelt on [including the back middle]
Sorry, the manual page is from 2020 Mazds CX-30. I have edited the post to make it more clear.
 
Sorry, the manual page is from 2020 Mazds CX-30. I have edited the post to make it more clear.
Ok, thanks for updating
So does the warning icon on the CX-30 show which individual door(s) are open [I saw the 3 icons on the manual page and maybe jumped to a wrong conclusion that it did]?
 
Just to clarify a few things....

TPMS sensors in the wheel are typically on the inside of the wheel but integral with the valve stem. They have non-replaceable lithium batteries which should last 5-10 years. For most, they should last between tire changes and tire shops will should always recommend they be replaced with new tires. I recall the cost of the sensors (with built in batteries) was about $10 each. There is a reset procedure to pair them with the car but tire shops should have all the equipment needed... you don’t shouldn't have to go to the dealer. Ham-fisted tire techs do occasionally break one when dismounting a tire (I.e., to fix a puncture) but shouldn’t if they have an up-to-date tire machine and proper technique. Go to one of the major chains like Discount Tire and you should be fine.

I’m also disappointed that there is no direct readout of tire pressure on my 2021, either on the dash or with the MyMazda app. It’s a chintzy omission.

- Mark

FIFY (fixed it for you)

$10 for the in-wheel sensor? You sure about that price?
 
Ok, thanks for updating
So does the warning icon on the CX-30 show which individual door(s) are open [I saw the 3 icons on the manual page and maybe jumped to a wrong conclusion that it did]?
Not sure on CX-30. The manual listed 3 different icons for 2-door、4 door、and trunk / hatch / liftgate. On my 2016 CX-5 it can’t distinguish which door is agar like my 2000 BMW does, but it tells me the liftgate is ajar if I remember it correctly.
 
FIFY (fixed it for you)

$10 for the in-wheel sensor? You sure about that price?

That’s what I paid six years ago at Costco during a tire change (a Honda with wheel sensors), but I’m not totally sure what was done (the car is 16-yo and I’ve had zero issues with the sensors). But it appears the previous posters are correct.... $60 is more like it insofar as list price (although I see a lot of options for lower-cost OEM or aftermarket, down to $20 or so). I’m curious if anyone has any recent experience at Discount or Costco doing a four-wheel tire purchase with new sensors.

Makes me view wheel speed differential systems more favorably, especially if Mazda doesn’t give you the benefit of displaying actual tire pressures.

- Mark
 
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Seeing the above ajar [top left] text from Nissan manual reminded me of another similarish lack-of-specificity on the CX-5 - it doesn't show which door is not properly closed when the red light comes on [again, presumably the system 'knows' which door(s) triggered the warning]
To correct myself [which is a nicer way of saying I was wrong!] my 2021 CX-5 does show which individual door [and/or the tailgate] is open - it's a second icon that only appears above the econometer when a door is open (which has a small red icon for each of the open door(s))
Below image is when I opened the driver door only i.e. the right red 'arrow' is the icon I knew about (smallish but stands out as red), the left orange arrow indicates the icon I didn't notice until later (although the car shape is big, it doesn't stand out as white - the red door indicators on it are pretty small)

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Don't see the advantage of having 2 icons

Apologies for the original duff info
 
To correct myself [which is a nicer way of saying I was wrong!] my 2021 CX-5 does show which individual door [and/or the tailgate] is open - it's a second icon that only appears above the econometer when a door is open (which has a small red icon for each of the open door(s))
Below image is when I opened the driver door only i.e. the right red 'arrow' is the icon I knew about (smallish but stands out as red), the left orange arrow indicates the icon I didn't notice until later (although the car shape is big, it doesn't stand out as white - the red door indicators on it are pretty small)

View attachment 298996
Don't see the advantage of having 2 icons

Apologies for the original duff info
I think it is laziness/cost cutting. The red light appears to be an idiot light that comes on every car regardless of the instrument cluster type, whereas the white icon with red door is part of the instrument clusters with (at least in 2021) the large Type A multi information center display
 
Inflating the donut to 60psi scares me. You can fit a full size 205mm width spare with 6.5-7" wheel in there by removing the foam blocks. I looked at using a 225 but it made the cover stick up a bit.
 
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