CAN BUS

[Mattin Adhami]

Hi, ive recently discovered a problem with my CAN bus system, however tesla and other cars seems to be quite different.
I had some questions regarding the CAN bus system, as tesla have 5 CAN systems. And I'm experiencing trouble with my drivetrain CAN (CAN 3), is there any way that if one CAN system experiences fault it can affect the other 4 systems?
As when the car is off there are THC and RCCM error codes, but when the brake is pressed, every single unit on the DRivetrain can bus goes into error and gives fault codes. Ive measured the resistance and voltage for can high and low.

For pins 18/19 (CAN 3), its correct, however if u measure at the OBDII port under the driver footwell, between CAN high and low I get a 120 ohm reading, which doesn't seem to be correct.
Anyone have any ideas on what I could do?

 

[vcor]

The ODB port CAN connections are worthless. There is no data worth looking at. You need to connect to the diagnostics connector (white). It's in the center console area on the S/X (varies a little depending on the vehicle variant). I'm fairly sure 120 ohms is the normal termination resistance on CAN buses, but I've not tested it myself. My CAN reader has the option of 120 ohm terminators, but I leave it disconnected.

The MCU may be able to transfer some CAN bus signals from one CAN bus to another, but I'm not aware of this being done. Perhaps someone else knows for sure.

Can't say I've heard of a similar problem though. Perhaps there is a short between the CAN bus and some other wire like the brake lights.

 

[brainhouston]

This is like 3rd thread u started about this issue...
U know u can just ask mods to change title if u didn't like the original...

 

[Mattin Adhami]

This is like 3rd thread u started about this issue...
U know u can just ask mods to change title if u didn't like the original...

Oh i didnt know sorry, im fairly new to the site. Thanks for the heads up

 

[brainhouston]

Oh i didnt know sorry, im fairly new to the site. Thanks for the heads up

u can also ask them to merge threads