Brainz

There’s been a lot of talk on the forums about how annoying the low tire pressure warning is on the factory TPMS system on the Porsche 997. While I like seeing the tire pressures, and usually drive with them displayed, I hate seeing the exclamation mark warning because the car thinks I’m 1 psi too low.

These instructions allow you to add new custom TPMS settings with lower pressure thresholds. I’ve not tried it, but I expect these instructions also work for the 987 Porsches as the electronics are similar, if not identical.

Credit for this idea goes to @semicycler – he’d posted about this, but I’ve never seen the instructions on how to actually do it. It does require PIWIS II to do coding on the car – so you’ll need to go to the dealer or find an independent or friend that has access to PIWIS II. Special thanks to @jeebus31 who let me use his borrowed PIWIS II.

WARNING: I’m just sumdood on the internet. I don’t own PIWIS II, am not an expert, and can’t help you troubleshoot if this doesn’t work for you. You should expect that the below instructions will ruin your car and/or get you or others killed. Proceed at your own risk.

The instructions below are what worked for me -- once I figured out what to do, it takes less than 10 minutes to execute. There may be other, simpler methods. I made a video in case you’d prefer to watch -- it’s crap quality but you can follow along in real time:
Instructions:

1. Find someone with a PIWIS II diagnostic system and hook it up to your car (OK – this may take more than 10 mins..)
2. From the PIWIS startup screen, select “Diagnostics” from the home screen menu and follow the sub menus to select 997 (or 987 as relevant)
   • The PIWIS will take about 30 seconds to connect and populate a list of systems for the vehicle
3. Once the systems are done populating, press F7 or select the “Add. Menu” button from the bottom-middle of the screen
   • This is important – don’t miss this step
4. The next screen will ask if you want to create a VAL. Press F11 or select the “No” button in the bottom-right of the screen
5. Select “Vehicle Handover” on the next screen and press F12 or the bottom-right button
6. After the list of vehicle systems populates, press F12 or the “Next” button in the bottom-right
7. The next screen should give you the option to Wake Up – Press the F8 button or the one labeled “Execute” in the bottom-middle
8. For each of the following screens, press F12 or the “Next” button that’s at the far right of the bottom of the screen -- you want to skip these
   • “Start MOST system test” screen
   • “Remove top speed limit” screen
   • “Deactivate Radio diagnosis gateway” screen
   • “Code Rear” screen
   • “Set tank correction value” screen
   • “Vehicle handover”/ “Is this a new vehicle?” screen
   • “Check chassis number” screen
   • “Is the chassis number correct?” screen
   • “Switch to log management” screen
9. Once you see the “List of logs” page, press the “Back” button that’s second from the right at the bottom – There’s no more options to move forward through
10. You should now see a list of all the electronic modules in the car; Scroll down and select the “Instrument Cluster” and then hit F12 / “Next”
    • NOTE: The Instrument Cluster module holds the TPMS warning thresholds -- not the TPMS module!
11. Once the Instrument Cluster control unit overview loads, select the “Coding adaptations” button from the upper right of the screen
12. From the Control unit coding screen, select “General Codes” and then “Next”
13. From the Coding/adaptations screen, select “TPM” and then “Next”
14. The next Coding/adaptations screen will have 10 options. Select all 10 of them (you may have to scroll down) and then “Next”
15. The next Coding/adaptations screen is the “money screen” – this is where you change the values. I coded mine as follows:
    • Menu selection: special summer tyres Value: Select “yes”
    • Menu selection: special winter tyres Value: Select “yes”
    • Menu text, special summer tires Value: Type in “Low Press “ <- Note: Must be 10 chars, there is a space after the last “s” in Press
    • Menu text, special winter tires Value: Type in “Low Press “ <- Note: Must be 10 chars, there is a space after the last “s” in Press
    • Nominal Pressures, spec. summer tyres, rear Value: Enter “2.3” <- Note: This is the warning threshold in bar (~33psi).
    • Nominal Pressures, spec. summer tyres, front Value: Enter “1.9” <- Note: This is the warning threshold in bar (~27psi).
    • Menu selection summer load Value: Select “is displayed”
    • Nominal Pressures, spec. winter tyres, rear Value: Enter “2.3” <- Note: This is the warning threshold in bar.
    • Nominal Pressures, spec. winter tyres, front Value: Enter “1.9” <- Note: This is the warning threshold in bar.
    • Menu selection winter load Value: Select “is displayed”
16. Once you’ve made all the changes in step 15, you should see a “pencil” in the changed column next to the entries that are to be uploaded. If you’ve confirmed your settings, press F8 or click the “Write” button at the bottom of the screen. Your gauge cluster will now go dark and reboot.

Congrats! You should be all done – confirm it works by doing the following:

1. Using the lower-left stalk behind the steering wheel, pull up the TPC menu on the gauge cluster. Select “TPC” and select “Set”.
2. At this point you’ll see two options: Summer and Winter tyres. Pick one. I usually use Summer (and select “continue”). The next screen will reveal two additional options:
   • 19” (or whatever is coded to your car from the factory) – Factory pressure setting is 33F/39R (in psi) on partial load; 36F/43R on full load
   • “Low Press” – This is your new custom pressure option – 27F/33R on partial load; 30F/37R on full load.
   • Select your desired option and select “continue”
3. You can now check your settings by selecting “Info pressure” from the TPC menu and it will show you what pressure settings are being used.
4. Note also that by changing the “Load” menus selection in the TPC, you can add 3-4 psi to the warning thresholds by selecting the “Full load” setting

Additional notes:

• You can set your own labels and pressures in step 15 above. Just make sure your custom label (eg: “Low Press “) is exactly 10 characters long – spaces count as characters.
• You can also set your own pressures – I chose 2.3/1.9 bar as that seemed to be low enough for my purposes (without going too low). If you’re a track rat and start with super low pressures, you might want to go with a lower figure. Also, for more options, you could set the winter tires to be different “Low Press” values than the summer tires.
• You’ll need to drive your car to relearn your TPMS sensors after doing the above. It usually resets in less than 10 miles of driving.

I’m pretty happy with the change. Hope to see fewer annoying TPMS warnings.

Hope that helps someone.

For202fly

I could really do without TPMS on any of the cars I have. Thank your for this. I'm with you, so annoyed.

chuzo

Thank you for sharing this.

Brainz

The instructions above are only to modify/reduce the tire pressures that trigger the TPMS warning in a working system.

For those that want to remove TPMS entirely, there are several posts on how to do so. The general process is as follows:

1) Unplug the TPMS module (silver box located adjacent to the master cylinder in the frunk)
2) Using your favorite coding capable scanner (PIWIS or Durametric Pro) to:
- Remove / code out TPMS from the Gateway
- Remove / code out TPMS from the Instrument Cluster

Links on the TPMS removal process here:
https://rennlist.com/forums/997-gt2-...ric-6-pro.html
https://rennlist.com/forums/diy-subm...etric-pro.html
https://rennlist.com/forums/997-gt2-...ml#post5235757

jayi836

Thanks for the hidden or additional menus will be coding mine soon.

Brainz

And thank you -- I believe it was your PIWIS that Jeebus borrowed (which I borrowed)!

jayi836

Haha-guilty, glad to have the information out there.

hestenet

I'm definitely a track rat, so I tried this out to add a "Track" tire type (with appropriate extra spaces in the name)

Getting some weird behavior. The sensors seem to work with "full load" checked, but with it unchecked I get "system not activated"

The stock TPM settings all still work.

Any ideas?

​​​​​Is it possible there's a minimum pressure at which the system is willing to work at all?a

Brainz

What pressures did you set? Did you try the pressures I used in my example instructions?

hestenet

For track days I run as low as 22 psi (1.5 bar) so I tried setting 1.8 bar for 'standard' and 1.5 for 'comfort' pressures.

On standard, and with full load checked, I could get a reading, but without full load checked it just says 'system not activated' which is what makes me think there's a lower limit or something...

EDIT: This is in a 981 Cayman S

Brainz

Sorry. I dont have access to the PIWIS any more or I'd try your pressures and see what happens. It's plausible there may be a minimum given that the higher setting works.