RotorMotor

I searched and searched and found lots of threads about people trying to disable the tire pressure sensor alert light for those that have changed their wheels, but wasn't able to find any success stories. Is anybody aware of a how-to for successfully disabling it?

And for the record, since there's been much debate about how the car reacts with no TPMS sensors, I get 5 short beeps when I first turn on the car and the yellow indicator light stays lit the entire time. It's easy to ignore, but I'd rather not have an idiot light staring at me while I'm driving....

Cerestes

Really? Interesting. My tires are changed, I get no beep and the light eventually starts blinking at me if I drive long enough. My understanding is if it does what you say it's doing there is actually some kind of malfunction. But I could be wrong.

Can't wait for summer and my 18's back

mamccubbin

I have my winter wheels on and I too just get the flashing light after several miles.

th1rd3y3

that's how mine is too

Sputnik

Thirdeye, check your PMs...

---jps

red_rx8_red_int

RotorMotor, did you just recently change your rims or has it been a while. I put my winter wheels on several months ago and up until a few weeks ago, I had what the others in this thread are saying. Start car and everythings fine, after a few miles the light blinks. But recently the light stays on the entire time. No beeps though. Today I did a poor mans ecu reflash, disconnected battery, pressed brakes to discharge any capacitance, and then re-connected the battery. Started the car did the dsc wheel thing (the tire light was on steady), turned the car off, restarted, dsc was OK now, but tire light still on!

The way I figure it it's one of two things 1. After having the sensors off for a set number of miles, the light stays on permamently until a signal from the sensors is received, or 2. I have a true problem with my system.

I've put aboyt 3k miles on with the stock wheels off. Also, I park right next to my stock tires in my garage. I'm going to call my dealer shortly but wanted to see if any one else has experienced this.

RotorMotor

Interesting. What happened with me was that I blew a tire hitting a really big rock on a club drive. This is what initially caused the TPMS light to come on because, clearly, there was no pressure in the tire. Because the bead was split and the rim was bent, one of the guys lent me a donut spare from an FD. The entire time that I had the donut spare on, I got the 5 beeps and the steady light. When I had the new rims put on (all of this happened over the last 2 weeks) the TPMS continued in the same manner: 5 beeps when I turn on the car and the light stays on steady. I'll try resetting the ECU tonight and see what happens....

rx8cited

Hi red_rx8_red_int and RotorMotor,
I wonder if following the Wheel Unit Autoregistration steps from
Tire Pressure Monitoring System Service Tips 2004
http://www.finishlineperformance.com...02-002-03.html

a) Turn ignition switch on.
b) Turn ignition switch off.
c) Leave vehicle with engine off for more than 15 minutes.
d) Drive vehicle for over 25mph for more than 10 minutes to register new ID codes.

would "RESET" the TPMS? If you try the above, please post your results.

Thanks,
rx8cited

PS: If have sensors on my wheels, so I cannot easily try it on my car.

RotorMotor

I believe those procedures are for when you replace an existing sensor with a new sensor, not when you remove the sensors all together. I've turned the engine on and off dozens of times and it hasn't reset.... Thanks for the info though.

rx8cited

hello RotorMotor,

That's correct - so I was thinking that trying the autoregistration might make the TPMS look for the sensors again.

I was wondering if turning the key to on, then back to off (without starting the car), then waiting 15 minutes before starting the engine would be different than just your normal car on, drive, car off, wait 15 minutes or more. Maybe both actions are the same as far as resetting the TPMS, maybe not? Figured it was pretty effortless for you to try.

regards,
rx8cited

RotorMotor

Yeah, what the hell. I'll give it a shot! :D

TreknMazda

RotorMotor,
If I am understanding you correctly, you have just one wheel without TPMS. If true, then maybe you are getting a different malfunction warning because only ONE of the TPMS is not detected.

RotorMotor

I had one wheel without a sensor (a spare) that was on the car for 4 days before I had 4 new rims installed, none of which have the sensors.

red_rx8_red_int

Great idea I forgot about the tpms reset/learn mode thing. I'll try it. On the other hand, I'm also thinking that could be what triggered my light in the first place! Here's my thinking:

Car initially set with new sensors at manufacturer, everything works right. New wheels put on, car searches for signal while driving and doesn't find them after certain amount of time and flashes (what used to happen to me and still happens to everyone else it seems). Somehow I turned key on but did not start car, stated car at least 15 minutes later, tpms goes into reset/training mode, does not receive the signals from the tires and sets the light to stay on. The only way to fix this is to put the original wheels back on and reset the system, wait the 15 minutes, and drive for a while.


This makes perfect sense. Does any one whose light just blinks after a period of time want to test this? Or for that matter, if RotorMotor tries this and his light now stays on but he has no beeps anymore, then that would also support my theory.

eskimo

I didn't get winter tires this year because I wanted to wait until I could get a wheel/tire/sensor combo (17"), mounted and balanced, from tirerack. They told me next winter. I have an old Protege I can bounce off snowbanks and curbs.

Well, when it started getting cold (below 0F) a few weeks ago, my TPMS light came on - beeps, then steady. I checked the pressure, and it was OK. I thought it had something to do with the cold. And yes, the light goes off after driving awhile - after it warms up. Hell, if the light is going to stay on anyway, I'm not going to spring for the sensor.

BTW red_rx8_red_int, I don't think parking next to the old sensors would do it - I remember reading that they're activated by centrifugal force when driving.

rx8cited

hi eskimo,
Lots of us with winter tires on our wheel that have TPMS sensors including TreknMazda and myself don't have our TPMS light come on for no reason - so it's not wasted money IMHO.

Did you check the pressure when the stock tires were cold or after you had driven for a while? I'm guess you checked them after driving when they were warmed up - a common mistake.

They should be 32 psi when cold (before you drive). If you park in a garage and check your pressure when the car tires are at garage temperature, then for every 10 degrees warmer your garage is above the outside ambient cold temperature, add 1 psi to extra above the normal 32 psi.

Other people that posted the same complaint as you later found that their tire pressure was set too low because they had not adjusted it correctly for the winter temperature drop.

hope this helps,
rx8cited

PS: I suggest using an accurate digital tire pressure guage - don't rely on the guages at a service station. For us with snow tires, they get 34 psi vs the stock tire 32 psi.

RotorMotor

Ok, I just tried the first part of rx8cited's suggestion. I turned the key to the On positions without starting the car, let it sit there for 10 seconds or so and shut it back off. We'll see what happens when I leave work today. I'll post the results as soon as I get home.

rx8cited

Hi RotorMotor,
Hope you had a good commute home.

Darn, I forgot to say you have to hold your left ear and count to 10, then walk around the car counterclockwise 3 times for this to work! J/K :D

I'll keep my fingers crossed for you .

rx8cited

Omicron

Ya know, what I'd like to figure out is how to disable the TPMS completely. When my Bridgestones wear out I plan to get run flat tires, and may well go with aftermarket wheels at that time.

Near as I can tell, there are 2 possible ways to do this: Fool the ECU into thinking the TPMS sensors are there and operating, or disable the TPMS system entirely. I think the latter case is possible as Canadian cars come without TPMS at all. So perhaps a code can be sent to the ECU to tell it to forget about the TPMS, or more likely there is a separate receiver somewhere for the TPMS signal. If this reciever is unplugged, the ECU may ignore the entire subsystem.

In the former case, we should be able to find out what frequency the TPMS sensors broadcast on with a frequency scanner. Does anyone have one that would be willing to do some investigative snooping? I'll bet the sensors all broadcast on the same frequency, and are not individually identifiable to the receiver, otherwise our system would probably alert to a particular tire being low.It probably just looks for 4 signals, and if one is missing, it alerts.

So we need to find out where the reciever is, and what frequency the sensors broadcast on. Once we have this info, we should be able to figure out a way to disable them completely.

RotorMotor

I want to disable it completely too!!!! Good suggestions on where to start Omni. Unfortunately I don't have the tools to help, but I'm sure somebody on this form does.

Anyway, back to the results of rx8cited's suggestion. Very interesting, not what I expected at all. I turned on the car and the beeps are gone, but the indicator light is still lit and is still solid as opposed to blinking. I'm stoked that the beeps are gone, but the light is still mildly annoying. I, quite honestly, didn't think that the procedures would do anything but I'm really glad you suggested the rx8cited. It brings us that much closer to a solution.

The sensors all communicate with the ECU over RF, right? I wonder what, if anything, else in the car uses RF to talk to it. Perhaps tracking down and removing the RF receiver would throw an error to the ECU that would would disable the light as well. It would seem that the programming of the ECU (fuel maps aside) is probably identical for the North American cars. If the Canadian cars don't have the sensors, maybe it's just because there's no RF receiver. Thoughts? I'm gonna see if I can find it and remove it. I'm booked tomorrow, but maybe I can get to it on Sunday.

red_rx8_red_int

I think it worked exactly right. I tried the thing today and nothing different. I am positive that when the tpms is reset it keeps the symbol on solid until it receives signals from 4 wheels and stores the communication codes from each sensor. Then on subsequent start ups it waits for a while and if it receives no signals from the 4 sensors then it flashes until turned off. This repeats on additional subsequent start ups. However, if it receives signals from some sensors, it makes the light stay on and beeps on start up. Probably the number of beeps tells what error it found. Evidently 5 beeps means it received 3 signals only.

I now have no doubts that some time over the last several weeks for some reason I turned the key to on and did not start the car. Maybe during my radar detector install.

To the person who posted about the wheels must be in motion, this is exactly right. My only solution to get rid of the light is to put the stock tires back on for a trip around the block. For the rest of this winter I'm going to place a small piece of electrical tape over it. For next winter I'll make sure and not reset the tpms. Or, more likely, I'll have sensors put in the winter rims over the summer. I agree with the person that posted about the tpms coming in handy. Before I put the winter setup on, the tpms twice warned me my tires were low. I am not a person that (at least before) regularly checked my pressure. I would say I checked 2-3 times a year at most. IMHO I prefer having the tpms active.

rx8cited

I'm glad you're got something positive out of this.:D I was not sure what would happen either, but I was guessing the light would start flashing again to indicate a TPMS malfunction (four missing sensors). Do let us know if the beeping comes back some other TPMS change occurs.

Yes.

I cannot imagine anything else using a RF link besides the homelink system. RF is expensive compared to running wires.

Are you folks not worried about invalidating your warranties by pulling RF receivers?

I hope the engineers designed the car well enough that if the RF receiver failed, it would be detected as a system malfunction which would cause something on the dashboard to light up and beep.

regards,
rx8cited

rx8cited

Any reason why you would not move your sensors from the stock wheels to the aftermarket wheels (I'm guessing the sensors fit many, if not all aftermarket wheels)?

Here's another thought: Remove the TPMS sensors from the wheel, try and hack them to transmit "tire pressure okay" RF signal and have them operate on the car battery when you turn the ignition on - packaged and located into the trunk.

regards,
rx8cited

Omicron

No, they will not fit a lot of wheels that are currently on the market. At least, not the reasonably priced ones.

Yes, this had occured to me. Tis a thought, altho I'd rather find and/or fool the receiver unit without the sensors.

rx8cited

Where does one find out which wheels accept the Mazda sensors - besides www.tirerack.com ?

Do you or anyone else know if all of TireRack's wheels listed for RX-8s accept wheel sensors, or do we have to ask for that info?

thanks,
rx8cited