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-   -   TPMS sensor ID save location - Possible solution to our TPMS problems? (http://legacygt.com/forums/showthread.php?t=104714)

Mr. Sinister 01-27-2009 11:37 AM

TPMS sensor ID save location - Possible solution to our TPMS problems?
 
Hello all,

I've been kicking around this idea in my head after picking up a set of winter wheels and was wondering if it would work.

First, does anybody know if the TPMS sensor IDs are registered/stored in the TPMS computer/receiver? The one that's under the driver seat?

If it is, we could just buy a second computer, have a second set of TPMS sensors registered to it, and just swap computers when we swap wheels. Ideally, we'd have a switched 'Y' connector so we could just toggle between the two and not deal with taking the seat out to swap computers. The computer costs just over $50 and this would be a cheap solution to implement. Thoughts?

Mods: You can move this to the wheels/tires section if you wish, but I figured it would get more attention here.

vr4Legacy 01-27-2009 03:22 PM

This is a GREAT thought and would be a wonderful solution. I sure hope someone knows the definitive answers. I'm sure this will get plenty of attention. I hope to get rims this summer and have dedicated summer tires. Hopefully you have solved my problem.

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DrCloud 01-27-2009 03:31 PM

I have a Nav system unit (the DVD part) under my driver's seat. Is the TPMS computer there as well?

That said, this could be a solution to this vexing issue, although it wouldn't surprise me to see a relatively cheap programming tool appear pretty soon. I'll stay tuned. HPH

Mr. Sinister 01-27-2009 03:54 PM

I haven't actually checked, but everything I've read so far indicates that it's under there. The GPS unit is pretty far towards the back, so I would suspect that the TPMS unit is either in front of it or partially under it.

rs6er 01-27-2009 04:00 PM

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ilh 01-27-2009 04:57 PM

How much you want to bet the TPMS computer is "married" to the BIU (body integrated unit) computer?

Hopefully not. A $50 part that allows folks to switch summer/winter wheels themselves sounds like not a bad deal.

--Lee

el5y 01-27-2009 05:18 PM

ilh - way to try and burst the bubble mr pessimistic :P I too would love to know if this is possible cuz then I could actually get my summer/winter set up

Eric

spongemonster 01-27-2009 05:24 PM

Hahaha I was so concerned with finding a proper tool to reset the computer for new sensors I never expected the computer for it to be so cheap.

GTurabus 01-31-2009 10:19 AM

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Mods, please consider moving this to the Wheels/Tires forum, with the other TPMS threads, as the other members that have been looking into this problem and contributing may be able to help and may have not regularly check the general Legacy forum (thinking of Opie to come up with the part number for the ECU). This topic has come up numerous times, and this seems to be as close to a real solution as I have read about.

The only other solution that was suggested before that I have been considering was a manifold where the TPMS sensors are all mounted and then pressurized through regular air fitting. The rather large air bottle pictured in the other thread may not be needed (so it could be mounted in the spare tire well), and an aspiring inventor/machinist/engineer/vendor could come up with a very useful mod for a small investment in time and materials that would likely find a number of potential customers through this web site. My recession adjusted one and one half cents.

Bbc84 01-31-2009 11:38 AM

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LGT Dave 01-31-2009 12:09 PM

This is an interesting idea, especially if the computer is only around $50. Like ilh said, I wonder if this computer is integrated into the BIU. I would actually be surprised if that were the case because there are only a handful of manufacturers of the TPMS systems and they are shared across multiple car companies. The only other thing to worry about is if the sensor ID's are stored inside this computer then are the ID's saved even after unhooking the computer from the car? I have a feeling that won't get answered until someone decides to be a guinea pig and actually try this.

Quote:

Originally Posted by GTurabus (Post 2278831)
The only other solution that was suggested before that I have been considering was a manifold where the TPMS sensors are all mounted and then pressurized through regular air fitting.

It would be nice if that would work, however the sensors are normally off if they are stationary. They only turn on and transmit while the wheel they are mounted to is rolling (over 25mph). Just having them sit in something pressurized wouldn't work unless you could get them rotating fast enough to turn on as well

GTurabus 01-31-2009 03:34 PM

[/quote]It would be nice if that would work, however the sensors are normally off if they are stationary. They only turn on and transmit while the wheel they are mounted to is rolling (over 25mph). Just having them sit in something pressurized wouldn't work unless you could get them rotating fast enough to turn on as well[/quote]

Well, I guess this is where the accessory powered electric motor comes in;).

On another note, now that I have my winter tires installed on my Tarmac IIIs without TPMS, the TPMS sensor on the dash will begin flashing for about a minute before it comes on steady. With the stockers, it never flashed, as I recall, and only came on briefly during start up. Someone who still has the stockers with the TPMS please try this (or I will this spring, when the stockers go back on). Start your car and drive in a parking lot and never exceed 25 mph (would be lucky to hit 10, usually). Does your light go on, not go on, blink, not blink? If the TPMS doesn't start sending until 25 mph, is the default not to flash at all?

I would think the ECU would also have to be able to detect the presence of the TPMS unit prior to motion, otherwise I should have experienced the flashing prior to the tire/wheel swap (until of course I hit 25 mph). I think the fact that it is no longer within range to send a signal would let the ECU determine(by absence of a proximity signal) it is not present, hence the immediate flashing, to differentiate between the absence of the transmitter(flashing) versus one that has not yet been activated by speed(no flashing).

Anyways, enough with this and somebody please find a solution before I put my daughter's Hello Kitty sticker over the dashlight:lol:.

ShadowImg 01-31-2009 03:36 PM

Since the TPMS computer is programmed with the SSM3, I would say the chance that it is integrated into the BIU are very high.

blackfang 01-31-2009 03:48 PM

1 Attachment(s)
Quote:

Originally Posted by ilh (Post 2271409)
How much you want to bet the TPMS computer is "married" to the BIU (body integrated unit) computer?

Hopefully not. A $50 part that allows folks to switch summer/winter wheels themselves sounds like not a bad deal.

--Lee

IIRC it is integrated/wired in with the BIU and the Combination meter under the knee bolster area.

Mr. Sinister 01-31-2009 03:55 PM

Quote:

Originally Posted by GTurabus (Post 2278831)
(thinking of Opie to come up with the part number for the ECU). This topic has come up numerous times, and this seems to be as close to a real solution as I have read about.

Part number is 28103AG01B per Jeremy of Fred Beans. The cost of the computer itself isn't bad, but I'd rather not buy a second set of sensors and get them installed only to find out it won't work. Ideally, someone who works at a dealer would test the idea.


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