X164 READING CAN BUS (B)
Thread Starter
Newbie
Joined: Feb 2019
Posts: 10
Likes: 1
X164 550 AMG
X164 READING CAN BUS (B)
Dear friends,
I got a lot of help here already. I hope this time, also someone has a bit time to help me and answer my question.
I was already digging around, but did not get the right information.
I like to read the CANBUS B of my my X164.
I prefer a direct "hook up" and not the ODB2 connector.
I have a MCP2515 CANBUS shield together with an Arduino mega.
The shield is working nice - with LOOPBACK or a second shield. (2 Arduino - one sender - one receiver)
I setup the speed to 125k.
I tried to connect to the CANBUS on the REAR SAM (10/8) - plug "G" PIN 16 and 26. My Shield has no termination resistor.
I connected H to H and L to L ( I tried the other way to make sure) - NOTHING.
I tried different libraries - one special for CAR CANBUS - NOTHING.
All I get is nothing! ;-)
Again LOOPBACK and communication between two modules (labor test) are working fine. But when it comes to the car - NOTHING.
I'm so sad!
Any suggestion what I'm doing wrong?
Is there a better point (trunk/rear) where I can get the CANBUS (B)?
Is there something at MB to use such a CANBUS sniffer? (my hardware and software is exactly the same, many project use for other brands).
THANK YOU SO MUCH! AND MERRY CHRISTMAS.
Alexander
I got a lot of help here already. I hope this time, also someone has a bit time to help me and answer my question.
I was already digging around, but did not get the right information.
I like to read the CANBUS B of my my X164.
I prefer a direct "hook up" and not the ODB2 connector.
I have a MCP2515 CANBUS shield together with an Arduino mega.
The shield is working nice - with LOOPBACK or a second shield. (2 Arduino - one sender - one receiver)
I setup the speed to 125k.
I tried to connect to the CANBUS on the REAR SAM (10/8) - plug "G" PIN 16 and 26. My Shield has no termination resistor.
I connected H to H and L to L ( I tried the other way to make sure) - NOTHING.
I tried different libraries - one special for CAR CANBUS - NOTHING.
All I get is nothing! ;-)
Again LOOPBACK and communication between two modules (labor test) are working fine. But when it comes to the car - NOTHING.
I'm so sad!
Any suggestion what I'm doing wrong?
Is there a better point (trunk/rear) where I can get the CANBUS (B)?
Is there something at MB to use such a CANBUS sniffer? (my hardware and software is exactly the same, many project use for other brands).
THANK YOU SO MUCH! AND MERRY CHRISTMAS.
Alexander
Super Member
Joined: Jun 2025
Posts: 784
Likes: 251
From: USA
Rear CAN needs ignition ON. Double-check pins: H to pin 26 (orange/black), L to pin 16 (orange/brown). A missing 120-ohm termination resistor on your shield is the most likely culprit add one. Always connect your Arduino ground to the car chassis. Test at the OBD port (pins 6 & 14) first to confirm your hardware works.
Thread Starter
Newbie
Joined: Feb 2019
Posts: 10
Likes: 1
X164 550 AMG
Hello Alexie,
Thank you for your response.
Just for me: Is this "how it should go" or did you try it this way?
The color code is not correct. The CANBUS at REARSAM N10/8 is BRAUN & BRAUN-RED (pe54.21-p-2103-97maa).
AFAIK - There should be just 2 resistors in one bus system - mostly at the beginning and end... all other devices are just "in the middle" and do not terminate the signale.
AT ODB - it's a different CANBUS right? Which speed should I use?
So, there is no Mercedes Magic or something else which keeps my data away ? ;-))) So, there is just some issue "somewhere" ;-(
Thank you for your response.
Just for me: Is this "how it should go" or did you try it this way?
The color code is not correct. The CANBUS at REARSAM N10/8 is BRAUN & BRAUN-RED (pe54.21-p-2103-97maa).
AFAIK - There should be just 2 resistors in one bus system - mostly at the beginning and end... all other devices are just "in the middle" and do not terminate the signale.
AT ODB - it's a different CANBUS right? Which speed should I use?
So, there is no Mercedes Magic or something else which keeps my data away ? ;-))) So, there is just some issue "somewhere" ;-(
