I've bought a couple of types of TPMS with mixed results.
First one was from a car accessory/speed parts store that specialised in the kind of stuff for 'rice-racer' crowd.
That brand of TPMS was called Orange, which was the in tyre sensor type.
My thinking was that being internal, and a largish unit at, that it would be more accurate and more durable/reliable.
They literally only lasted one day.
The day after fitting two stopped working early, then a third one also stopped leaving me with only the one unit showing on the display.
I was assured by the (likeable)chap at the speed store that this brand was very good.
Anyhow, back a couple of days later and showed him that they weren't working, he checked stuff I already did, but we couldn't get them going .. and he gave me another kit of the same brand without batting an eyelid.
That is without forcing me to get them uninstalled, bring them in, swap them etc. (I knew he was likeable for a reason .. genuine bloke!! [thumbsupbig])
I still have this replacement system too .. didn't bother to get it installed.
But what I did do instead, was order a cheapo TPMS system off ebay.
The brand is called CareUD. Valve cap system. Initially they kind'a looked silly having the large cap on the valve, but being silver they blend in fine with the colour of the wheel .. so that quickly became a non issue.
Had them installed for two years now, with zero issues.
Not only did that surprise me having worked perfectly for longer than just one day (as I was expecting) .. but they also do as they supposed too as warn me of low pressure in any affected tyre.
On a bit of a drive around the traps to leave the rat race behind, I stopped out at Cobar for some brekkie. About 30 mins out of town I hear a constant beep beep noise. Took me a short while to work out what it was too!
Early morning/late night syndrome on my part I guess, but in that 30mins I hadn't checked the TPMS display at all since leaving Cobar.
I remember noting that in Cobar they wee all good(I used to run 35-38 depending on conditions).
The beeping tone was the TPMS showing the front left tyre at 17psi(I have set it to warn below 18psi .. just in case I need to go that low in sand). And spot on at 18psi it warned me with it's beeping.
I'm the type that usually checks gauges and stuff quite often, but obviously not in the last 30mins .. good'o! on this neat little TPMS system anyhow.
Turned out I was losing about 30psi every 30mins/40klms or so on the rest of the trip towards Wilcannia, where I thought I'd get a tyre place to fix it. Couldn't find one so had to divert from my planned White Cliffs to Broken Hill instead to be sure I found a tyre place open and capable.
So I ended up doing about 400+ klms with a fast deflating tyre in 40+°C ambient temps, generally at 90-ish k/h ... and this cheap little TPMS did it's job all the way.
Note tho that my brother in law recently got a cheap TPMS off ebay recently too, and none of the monitoring caps worked at all(he reckons). Could be that he didn't know how to 'set it up'.
No idea on brand either. But they are plug'n'play.
Install them in the order on the cap, and wait for the Bt connection to finally take hold. They can take upwards of 15mins to register and a drive helps them too as well.
I'm about to get another set of these CareUD types for my dads car too .. so hopefully will be a good acid test to see if mine were just a lucky fluke, or if they actually are a half decent item.
ps. even tho it's been two years since that initial failed Orange TPMS system going into the wheels, I've yet to get the units removed!
A point to note too: the display(or head) units are the typical Chinese quality cigarette lighter plug crap. They're so badly made they sit too loose.
The (failed)Orange system had a separate head unit with a cabled connection to a power port of your choice. I replaced the cig lighter socket end on that thing tho.
The CareUD system I use has a head unit that is attached to, but detachable from, the plug if you want to run it remotely. I tried that, but found it more convenient to leave it plugged into the cig socket that the D1/D2 has down low. But on a bumpy road it falls out of the power port after about 30-60mins. To keep it in place properly it needs a 'wedge' in the power port. I use a small piece of cardboard wedged on the underside to keep it firmly plugged in.
I'd recommend trying a cheap 'cap system' off ebay. Cost is generally about $80ish for a 4 tyre system.
For a trailer system it could pay to get two systems and run them separately.. leaving two caps as spares.
Only issue I can see with using a TPMS for air bag monitoring is the upper and lower monitoring values.
They are 'fixed' in some systems in that they may only allow a lower limit of X(psi) and a upper limit of Y(psi).
Can't remember the upper limit, but as an example the lower limit on both my units is 18psi. I just can't remember the upper limit value.
So as an example if the upper limit was something like 60psi(as they are usually car systems) inflating air bags to 65 will have the unit beeping it's head off all the time.
if the upper limit is something like 80psi... it won't be a problem.
Same with the example given of 10psi .. being under 18psi that some systems may be limited too, it will beep all the time.
So whatever you choose, or are looking at, these specs will need to be taken into consideration.
Hope that helps.
