jasone36

Hello,

After many years, my TPMS light on my 2002 SC430 dash is now solid orange (I made sure all the tire pressure is correct all around).

My only conclusion is that the battery in one (or more) of the four TPMS sensors is dead.

Now I am wondering, is there any value in keeping the TPMS "plugged in", or should I just unplug it?

I've read some information saying that perhaps the system will still "buzz" or somehow warn the driver of a "catastrophic" tire puncture... does anyone know if that's true?

I don't mind staring at the orange TPMS dash light *IF* there's still some value to be had... but if there's absolutely none then I'll ask my mechanic to unplug it (as per the posts on this forum).

(At this point, I have no desire to spend huge bucks to replace TMPS sensors in a 15+ year old car).

Any insight would be appreciated.

Thank you!

Harold57

I would expect the monitor to continue to operate utilizing the working TPMs but then again I don't know that for sure. If you wanted to check it out, you could deflate a tire or two to something below 20 psi and see if the alarm goes off. (I've never heard it myself but others have reported it going off.)

Obviously, don't do this without a source of air to be able to re-inflate the tires...

mandyfig

Some of us who have deactivated the TPMS use the tried and true common sense approach.

Visually check you tires prior to driving; check air pressure every week at least. Once you get used to the VISUAL appearance of a GOOD inflated tire, then you can make a judgement of an abnormal looking tire (means less air pressure). This is hard to teach but after some training, you can at least be alert that one of your tires need attention. A good air tire pressure gage is a good tool to have.

Ask me about training...my kids have to hear me preach about being aware of your car's condition, and the result is still to be determined. I hope one day they will own up to the fact that they sensed something was wrong and they managed to address the issue prior to failure. I can dream, can't I?

Good luck.

Plan you trips. Punctures normally happens on roads and streets less traveled.

jasone36

Thanks for the responses, Harold57 and Mandyfig.

Unfortunately, we've had a ton of snow here recently, thus I'm not sure I can do too much testing (in terms of lowering the tire pressure, in order to watch for any triggers).

The common-sense approach makes sense, I try to check it manually whenever I can remember to (usually on sunny, warm days.... i.e. not during the NY winter LOL).

After having plenty of tire pressure issues due to warped OEM wheels (and having them straightened), I have been able to eyeball the tire pressure over the past 4+ years, but I've come to rely on the (now faulty) TPMS system more than I can admit.

This 2002 SC430 has been my daily driver for 4.5 years, and has rarely let me down, but the tire pressure has always been a pain point. Maybe this car just isn't designed to withstand daily driving in the northeast part of the country... but I'm doing it

Anyway, if anyone has any additional information on this topic, please do share with the group.

Thank you.

Bgw70

For what it is worth, I just installed a new TPMS sensor for $75.
Do you consider that big bucks...if so, I certainly understand...

Check out post 207 in this thread...
https://www.clublexus.com/forums/sc4...-system-6.html

Poqman

If I were running run flat tires, then I would keep the TPMS working. The stiff sidewalls of the run flats may throw off your visual inspection. The non-run flats side walls would give you the visual trigger. My TPMS is still working, but I carry a plug kit and air pump in the trunk where the spare would go. I triggered a warning on interstate last year letting me know I picked up a nail in my non run-flat. I had to pull over ever 40 miles and pump it back up until the next day when I dropped it off with Firestone, but it got me home. Great peace of mind.

Coleroad

This is why tpms is important if you have runflats. Remember it's probably only one not four. With the low profile of our stock size the feel of a flat runflat isn't easy to feel on normal driving. You wouldn't want to be on a longer drive and not know it's flat. Driven far enough it will come apart. Think if your on a 200 mile trip on the interstate and didn't realize you had a puncture.

Bgw70

Slightly off topic...
I had the Michelin PAX system on my 2006 Honda Odyssey mini van, I purchased it brand new. The first thing I did was purchase a set of normal Odyessey wheels on eBay for $200. I put them in the attic until I wore the pax tires out at 25k miles.
No one will service them anymore except for Honda and when they do, you must replace the tire and wheel together because the machines are hard to find...
Anyway, it was a big mistake for Honda and Michelin...

Back on topic, The TPMS sensors are personal preference if you do not have the run flats.
I like the sensors because they will let you know you have a nail before you notice the tire running low on air, plus it is not that expensive if you consider how long they last.
I know in a previous post someone said, why would I want to fix this on a 15 yr old car. Because, it is an SC430 and it is a nice car that will last a very long time if you provide the proper care and maintenance. But that is just me... :-)

texsexlex

iTrader: (3)

....if any of the other sensors are working,the system will continue to moniter. My light has been off/on for the last couple of years, but I hadn't bothered changing the batteries. About a year ago, I bought a new tire & the technician showed me the condition of the sensor, of the tire being replaced. It was pretty beat up, but I had him put it back on. A few days later, I was on my way home & the TPMS buzzer went off. I had run over a spike & it punctured a rear tire,but the system came on & worked as it was designed to do. I was pretty lucky because I was about to get on the highway..... that could have been a disaster waiting to happen

JohnnyCake

I'm at the same situation as the OP -- I'd like to hear more discussion on this topic. Here's some questions I have:

1. If the TPMS light is already on due to a sensor failure, how can it alert the driver if a "good sensor" tire has low air? The light is already on.

2. I have the same thing were the light is on/off. What's up with that? Isn't it a situation where the battery in the sensor has either failed or it hasn't.

OBP

Near dead batteries can fail to transmit a TPMS signal after a few successful transmissions. This happened to me on my OEM wheels with winter tires - somedays it would work initially but after driving for a while, the light would come on even though pressure was perfect. Cos the battery just stopped transmitting cos it got too weak.

jasone36

Thanks for all the responses so far.

texsexlex, would you please be able to provide more detail, specifically (as JohnnyCake stated):


1. If the TPMS light is already on due to a sensor failure, how can it alert the driver if a "good sensor" tire has low air? The light is already on.

In my case, I have non-run-flat tires, and when they loose air pressure I can kind-of "eyeball" it.

BGW70, getting a TPMS sensor replaced for $70 isn't bad... was it OEM or aftermarket? My thought is that if I were to start this TPMS replacing project, I would want to replace all four (rather than wait for them to die one by one), which could get pricey.

When I'm saying "pricey", I don't mean it in a general way.... but when we consider that the 2002 models are so old now, I feel like it's not a great investment.

I do plan on driving my SC430 for as long as possible... probably even after the hardtop stops working (I'm dreading that day), but unfortunately the high-mileage 2002 models are increasingly become "disposable" in that any type of major work on the car could eclipse the (wholesale) cost of the 2002 model.

You know how sometimes you drive through thoroughly blue-collar inner-city neighborhoods (i.e. the type where you see road-side billboards saying "Get your G.E.D." in four different languages... three of which you can't read) and you see 20+ year old "luxury" cars "perma-parked" with either no plates or woefully expired plates, well that's because the owners simply ditched them (often seen with late 80's/early 90's Benz's and Jaguars) due to sky-high repair costs on these once super-premium cars...

Well, I'm hoping the SC430 doesn't join that parade, due to it's excellent drivetrain (I have yet to see a Lexus "perma-parked" in the ghetto).

I'm banking on the fact that the drivetrain will last a while.

Bgw70

I purchased mine from Rockauto.com and it was the make brand and part number as the one I pulled out of the car.
There are four different colors on the sensors and I believe it has to do with the frequency they transmit.
You need tech stream or another device to figure out which one is bad.


See post no.207 in this thread
https://www.clublexus.com/forums/sc4...-system-6.html

Harold57

It seems like I've read about a couple of the owners indicating that there is an audible alarm that goes off beyond a certain point. I've never had that happen and other than on this forum, I don't remember reading about it, but I also haven't looked. (It is also possible that I'm mixing the audible alarm with another issue. )

texsexlex

iTrader: (3)

....now i don't know this to be 100%.....but I was under the impression that if the light was on, then it was indicating a bad battery in one of the sensors. You could technically have a bad/dead battery in a sensor,but the others still active. if the system detects low pressure,in one of the tires with a working sensor, then you should get the audible alarm. This is what I think happened in my case. I think the system is always active/working, as long as you haven't disabled it and if all batteries are good, it should be able to detect low pressure in any of the tires. If you have a dead battery in a sensor,it won't be able to alert you of low pressure in that particular wheel