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How TPMS is reset in the model S...

Discussion in 'Model S: Driving Dynamics' started by FlasherZ, Dec 13, 2012.

  1. FlasherZ

    FlasherZ Sig Model S + Sig Model X + Model 3 Resv

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    The ranger (Hi, Leo!) was out to work on my car over the past couple of days, to resolve the issues that I had. Part of this was a generic TPMS error that appeared from the moment the car was delivered.

    The procedure goes something like this:

    1. Using a hand-held programmer, called the "Tesla multi-tool", the ranger walks around to each of the tires and holds the tool against the valve stem on each wheel, presses a button, and the tool scans for the TPMS sensor ID. This procedure, if I recall correctly, starts with left front, proceeds to right front and right rear, then to left rear.
    2. Once all of the wheels are scanned into the tool and displayed on the screen, the device is plugged into a connector in the car below the touch screen, and the multi-tool pushes the ID's to the car's computer.

    There is also a service bulletin that has been published for the service centers to reduce the low tire pressure alert from ~38 psi to ~36 PSI to deal with pressure reduction due to cold weather. The same tool is used to program the TPMS system's parameters.

    For those wondering whether the Model S knows the individual tire sensor locations, the answer is yes -- they must be scanned in order.

    This gives us hope that some day, the tool may not be needed, if the touchscreen computer could interact with the TPMS to learn the sensors in the same way that my Chevy does -- flash the front left turn signal, then watch TPMS sensors until they report a reduction or increase in PSI of 1-2 PSI (while you add or let out air in the specified tire), then move to other wheels in order. That way, the special tool wouldn't be needed.
     
  2. AnOutsider

    AnOutsider S532 # XS27

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    That would be great. My wife's old murano could tell the psi at each wheel. I miss that
     
  3. mknox

    mknox Well-Known Member

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    My Cadillac works the same way - - must be a GM thing. Thanks for the report. Hopefully we'll see that in a future software update.
     
  4. Doug_G

    Doug_G Lead Moderator

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    Really? My old Murano had no clue which wheel was which, and they moved around the display every time you started the car.
     
  5. Robert.Boston

    Robert.Boston Model S VIN P01536

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    We used to call those things "tricorders". ;-)
     
  6. NielsChr

    NielsChr Member

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    3 questions about TPMS.

    what happen to TPMS if I change from summer to winther wheels ? can the Model S store multiply TPMS id's, so no reprogramming would be needed.
    what when I switch back again (e.g. winther / summer), would I require to mount the wheels in same order,I would personally do wheel rotation to minimice wear on the tires.
    Would it be posible to use non Tesla wheels

    - anybody know the answer ?
     
  7. dsm363

    dsm363 Roadster + Sig Model S

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    It currently requires a Tesla Ranger (or service center) to reprogram the wheels again (even if they've been programmed before). I heard they are working on a solution where you store two sets of tires (for example summer and winter tires) and once they are both programmed, you simple click 'switch to set A' and they will work. It sounds like it's simply a software issue so maybe auto learning is also in the works.

    You can use non-Tesla wheels but would need a sensor from Tesla and have them programmed.
     
  8. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    So far from the various posts it sounds as if they can't do that. It must be programmed for each wheel change. Apparently it can't store the information for two sets of wheels. The TPMS regulations are pretty lame when it comes to how wheels and tires are actually used, and TPMSs are typically made to conform to the regulations and no more. Perhaps Tesla will address this issue in the future. A robust tire monitoring and inflation system would be a nice addition to the Tech package in a future Model S.

    I don't believe it matters which position the wheel is in for the TPMS to work. The TPMS base system in the car doesn't keep track of which wheel is in which position.

    If you have the Tesla TPMS sensors for the wheels. The sensors have to talk to the base unit, and so far only the Tesla sensors are known to work. Tesla no doubt purchases the TPMS so perhaps someone will find out who makes it and what other sensors can be used (if any). Wheel sizing and other factors are discussed here and here.
     
  9. swegman

    swegman Member

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    What happens when you rotate the wheels? Vehicles I have had with TPMS provided information as to the tire pressure for each tire. For example, it may say the left front wheel is 40psi. What happens when you move the left front wheel to, for example, the left rear wheel position? Does the system need to be reprogrammed to reflect the new location of the tire, or does it automatically know where the tire has been moved to?
     
  10. dsm363

    dsm363 Roadster + Sig Model S

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    I had my tires rotated today and don't think he reprogrammed them. I'll ask him to double check though.

    - - - Updated - - -

    Talk about service. Sent my Ranger an e-mail (he had been up working until midnight on Friday and still drive the 90 min to my house to get there at 8:45AM) and heard back within 30 min.

    He said it is a good idea to reprogram the tires again after they are rotated so looks like you have to do that. An auto-learning function would be nice.
     
  11. swegman

    swegman Member

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    That really would be a pain if the TPMS has to be reprogrammed every time you rotate the tires. Would basically mean you can't rotate the tires yourself, which is something many people do.
     
  12. FlasherZ

    FlasherZ Sig Model S + Sig Model X + Model 3 Resv

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    The programmer requires the ranger to go to specific wheels (see the original post) and loads them into the computer in specific positions. That said, the warnings presented to users are not relative to the specific wheels ("low tire pressure detected"). So the system definitely knows which sensor serial number is in which position, but the control system may not give you that information as a driver.

    - - - Updated - - -

    Perhaps that's why they choose not to show you a specific tire location when it says "low tire pressure detected". As mentioned, the programmer requires sensing the LF, RF, RR, LR in that order before attaching it to the car and pushing it there.

    Based on how it's programmed and pushed to the car's chassis computer, it appears the TPMS is an independent "black box" module and there was no investment on tying it into the other systems in the car; hence the separate programmer.
     
  13. swegman

    swegman Member

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    FlasherZ, so if I understand what you said correctly, The car will not tell you the tire pressure in each individual tire? It only indicates a generalized low tire pressure, and you then have to check the tire pressure of each tire to determine which is the one that is low? I had a 2007 Infiniti and a 2010 Lexus that indicated the exact tire pressure in each wheel. If one tire was low on air, it told you which is the tire that was low. In fact, you could watch the pressure indications and how they increased from the "rolling friction" (not sure that this is the correct term) as you drive.

    Knowing which is the specific tire that is low on air is very helpful. The Infinity had one tire that would lose air over a 2-3 month period, just enough to trigger the alert, while the other 3 tires never lost enough to trip the indicator.
     
  14. FlasherZ

    FlasherZ Sig Model S + Sig Model X + Model 3 Resv

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    Yes, that is true. The error indicated is "Low Tire Pressure Warning" on the display.

    That doesn't mean the information isn't available to Tesla on the CAN bus from the TPMS unit, but Tesla chooses only to offer you that there is a low tire pressure warning. My wife's Chevy Traverse shows me (in the OnStar mobile app even!) the individual tire pressures for each tire.

    But, as mentioned, tire rotation comes into play. Any shop can rotate your tires, then reprogram the TPMS for new tire location by using the integrated reprogramming mechanism.

    Right now, Tesla is limited to this reprogramming via their $500 programming tool. For tire pressure to be accurate for wheel location, it would require the rangers to reprogram it every time you rotate the tires.

    I imagine it was a planned decision not to offer specific wheel pressures (although I would suggest if they ever built the capability to do this through the touchscreen that you would get individual wheel pressures at that point).

    - - - Updated - - -

    Here's a snapshot of the Chevy OnStar remote app... I'd like to see this in the touchscreen, if not the Tesla app too:

    Screenshot_2012-12-16-10-53-14.png

    (and yes, I'm aware it shows low tire pressure, it was cold, the last drive was only 3 mils, and we haven't done the cold weather pressure increase yet...)
     
  15. Brian H

    Brian H Banned

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    Very suitable pun! Nice one. :wink::biggrin:
     
  16. Chgd Up

    Chgd Up Sig 1004

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    I was able to go through the tire pressure activation today. Once switched into the diagnostic mode with the hand held tool as described, each of the wheels individual temperature and pressure were displayed.

    There appeared to be a number of other diagnostic options available on-board in the car. One of the most intriguing was a live flow diagram of the entire heating and cooling circuit. It showed the flow through the battery, inverter, motor, charger, chiller, electric heater, heat exchangers, and radiator circuits. It appeared that all the fluid circuits were interconnected We were able to watch the fans and chiller switch on and flow circuits switch. It was really pretty awesome to look at and a very complex system.

    Definitely some very cool stuff under the diagnostics mode hood.
     
  17. agileone

    agileone CDN P#40

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    #17 agileone, Dec 19, 2012
    Last edited: Dec 19, 2012
    Tpms oem ?

    No formal proof, but they do seem to be Baolong DF003. See last page of this pdf.
    See page 6 for the programming tool which we seems to be the same as sold by Tesla, for the Roadster : Roadster Tire Pressure Monitoring System Tesla Motors

    Baolong refers to Tesla as a client on their web site and this particular product also refers to Tesla in their application docs. See Customers page from the main menu.

    See the OE Solutions page, I bookmarked is here :http://www.baolong.biz/baolong_en/product_list.aspx?childid=200909170842221031&classid=200907231130299218&pid=200909141113081968

    From this doc, it seems Nissan China uses the same sensors in some vehicules over there : http://www.baolong.biz/download/20122241525302622.pdf
    special designed for Nissan cars;
    with Original equipment apperance;
    Nissan China approved;
     
  18. Chgd Up

    Chgd Up Sig 1004

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    Yes it looked very much like that except yellow. It is possible that a special configuration of the tool is required for the Model S. The tech said the diagnostic tools were in short supply like so many parts during the start-up and that he had a hard time getting one for the service location.

    Now if a Roadster owner with one of these tools and a Model S owner were to get together???
     
  19. FlasherZ

    FlasherZ Sig Model S + Sig Model X + Model 3 Resv

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    You also need a special cable that will connect the car's white diagnostic connector under the touchscreen to the DB connector on the multi-tool.
     
  20. Babylonfive

    Babylonfive Power12

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    I'm confused at some of the answers here, especially around having to reprogram on rotation... that seems wrong to me.

    The programming tool essentially identifies the pressure transmitter module physically - the process of going around the car and doing this (reading each tire, and then loading data in the car) links the sensor ID to the car receiver. Because the car keeps track of all four pressures, but doesn't show them on the screen by position, it doesn't matter if you rotate them. They simply continue to report their pressure irrespective of configuration.

    If Tesla showed each tire pressure by location, they'd either need a very directional receiver in each wheel well, or else give the customer a method for moving the link between ID and wheel well location after the rotation.

    In addition, if Tesla expects all rotations to be done at the service center, then they could reprogram with the tool to support future SW updates that might allow that positional pressure data to show. Otherwise with current software, they wouldn't have to rescan, even on rotation.

    I sure hope they look into this - it's harder to go to each tire, rather than the exact tire with the issue
     

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