A lot of good work has been done to decode the CAN, LIN and K-Line messages related to the 2.x Roadster TPMS system. We have a good understanding of how it works, and can manually manipulate things from the LIN and K-Line buses. In particular, we now know how to read and write tyre IDs from/to the TPMS ECU.
However, to make this useful we need to make a tool. Either something standalone, or an extension to OVMS. The protocol used by the TPMS system over K-line is not complex, but it is non-standard both in software (not based on ISO9141) and voltage (5V vs 12V).
I am very willing to help with this, but I quite simply don't have the car any more. If I did, I could probably knock up the solution in a weekend now. I know of a couple of roadsters in Hong Kong, but none have the TPMS option installed. There is one in China, but with the travel restrictions that won't be usable for the near future. All the other roadsters that I know of with TPMS are dead in the service centre waiting for new batteries.
I had hoped that my 2014 Tesla Model S would work as a test bed for this, but despite reports that the TPMS is the same, it is not. The tyre sensors maybe, but the ECU is certainly not.
I see two options:
Ideas / suggestions? @CM_007, @racevpr ?
P.S. My direct eMail is mark (at) openvehicles (dot) com, if anybody wants to suggest/offer off-list.
However, to make this useful we need to make a tool. Either something standalone, or an extension to OVMS. The protocol used by the TPMS system over K-line is not complex, but it is non-standard both in software (not based on ISO9141) and voltage (5V vs 12V).
I am very willing to help with this, but I quite simply don't have the car any more. If I did, I could probably knock up the solution in a weekend now. I know of a couple of roadsters in Hong Kong, but none have the TPMS option installed. There is one in China, but with the travel restrictions that won't be usable for the near future. All the other roadsters that I know of with TPMS are dead in the service centre waiting for new batteries.
I had hoped that my 2014 Tesla Model S would work as a test bed for this, but despite reports that the TPMS is the same, it is not. The tyre sensors maybe, but the ECU is certainly not.
I see two options:
- We collectively obtain an ECU + 2xantennas + cables, and use that to work from on the bench. The electrics are well documented, so bringing such a system up on the bench should not be hard. We could probably even do without the cables. These would have to come from a salvage car, or spare parts bins. This could be crowd-funded, or handled on a loan basis.
- Someone in USA / Europe takes on the hardware side of the project.
Ideas / suggestions? @CM_007, @racevpr ?
P.S. My direct eMail is mark (at) openvehicles (dot) com, if anybody wants to suggest/offer off-list.
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