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Communication networks

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Hi, I'm new here and this is my first post.

I'm interested in the electronic communication of the roadster. Traditionally OEMs use combinations of communication networks, depending on the purpose of the installation, for example a common multi-purpose serial communication standard as CAN, but also new upcomers like MOST for multimedia/infotainment and Flexray for X-by-wire applications is seen more and more, at least in european cars. Anyone who knows what solution Tesla has decided to go with?

I know that I've seen CARB being mentioned in technical blogs about the roadster, which suggests that there should be a OBD socket in the roadster, leaving an access point for scan tools. I haven't had the opportunity to sit in one, so I haven't had the chance to verify this. Anyone?
 
Welcome!

This is not information I have seen here before (although it seems like something TEG might know). The Roadster has a lot of proprietary stuff locked in the PEM - it would not surprise me to hear that they developed their own protocols for some standard communications.

Externally there is a USB port for onboard diagnostics. I do not know of any additional port internally, but that doesn't mean it does not exist. They have not published the protocols used by the USB port, and it is assumed it is non-standard.
 
There is an OBD port. It's under the dash in the upper right of the driver's side foot well (at least in the Validation Prototypes (VPs)). There's also the USB port graham mentions, it under the center console arch. Some photos from VP12 below.


OBD connector:
img0180connxz0.jpg



USB port:
img0119usbzi1.jpg
 
Externally there is a USB port for onboard diagnostics. I do not know of any additional port internally, but that doesn't mean it does not exist. They have not published the protocols used by the USB port, and it is assumed it is non-standard.
Is the USB-port you talking about only used for onboard diagnostics or is this where you're supposed to connect your iPod etc?
 
OBD2, CAN bus, other car network technologies

Someone posted this picture of the glove box of the Tesla/Smart prototype:
3488889952_58276e55a2_b.jpg

So we have OBD2 on the left, 3 CAN busses, and a USB connector for something.

Some of the more technically minded on this forum have asked questions about protocols used for car control, so I thought I would throw out some links of publications and projects useful if you really wanted to understand how this stuff works.

On-Board Diagnostics for Light and Medium Duty Vehicles Standards Manual - 2006 Edition
Card Labs - OBDII Resources
OpenDiag
OBD-II PIDs - Wikipedia, the free encyclopedia
prj.perquin.com
obd_connector.gif

Sample scan obtained of a SMART FOR TWO car


--wakeup
81 -> e9 8f
--get capabilities
01 00 -> b2 3f f8 11 capabilities service 1: 1 3 4 5 6 7 b v d e f 10 11 12 13 14 15 1c 20
01 20 -> 80 00 00 00 capabilities service 1: 21
02 00 00 -> 7e 38 00 00 capabilities service 2: 2 3 4 5 6 7 b c d
05 00 00 -> 7f 05 11 capabilities service 5: none
06 00 -> ff c0 80 00 capabilities service 6: 1 2 3 4 5 6 7 8 9 a 11
08 00 00 00 00 00 00 -> 7f 08 11 capabilities service 8: none
09 00 -> 01 30 00 00 00 ???? expected 4 byte response...
--get status
01 01 -> 01 07 69 00 MIL light off, 1 dtc, ready, no 02monotoring
--get dtc's
03 -> 07 02 00 00 00 00 dtc P0702
--scan sensors
01 03
01 04
01 05 -> 3a engine coolant temp = 18C (3a=58 dec - 40 dec)
01 06
01 07
01 0b
01 0c
01 0d
01 0e
01 0f
01 10
01 11
01 12
01 13 -> 03 2 sensors
01 14
01 15
01 1c
01 20 -> 80 00 00 00 (always same: capabilities 21-40)
01 21 -> 00 37
 
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I recall a picture of a Tesla employee using a USB stick with the Roadster. I think the USB stick is located near the floor in the middle of the car.

Anyone remember where the USB port for the Roadster is? If it exists - I only remember seeing a picture.