CAN Bus Basics: Getting Started

Hello,

My name is Phil, and I would like to delve deeper into the topic of CAN bus in the near future. I am familiar with the basic functionality of CAN.

I own various hardware and software, including OBD adapters and cables, MoDiag Expert, VCDS, and an oscilloscope (both lab and portable). I've worked on several small projects and built a few things. However, I'm not an expert – it's all a hobby. Please excuse me if some of my assumptions are incorrect.

When I read data from my Golf using VCDS, I get values such as injection time and injection quantity from the engine control unit. These and other specific data cannot be read with software like MoDiag. So, if I want to know which CAN messages these data points correspond to, I would need to intercept and decode the communication, correct? How exactly would I go about doing that? My idea is to use an OBD-Y cable and connect it to both a computer with VCDS and a CAN sniffer with software. Then, I would request the desired data using VCDS and simultaneously log the communication. Does that sound right? Or am I making a mistake here? And what would be the next step?

Is there any introductory literature available on this specific topic?

Best regards,
Phil.

Buch "Bussysteme in der Fahrzeugtechnik

Protokolle, Standards und Softwarearchitektur

Reihe: ATZ/MTZ-Fachbuch

Zimmermann, Werner, Schmidgall, Ralf"

und dieses Forum hier.

Viele Grüsse, Rainer

Hello Rainer,

Thank you for your reply. The book is available at our library. I will borrow it as soon as possible.

If I order the RKS+CAN interface along with the KCANMonitor, will that help me progress with my experiments? And is there a detailed manual for the software?

Best regards,
Phil.

Hallo Phil,

KCANMonitor ist größtenteils selbsterklärend, im Programm gibt es eine Hilfe:

RKS+CAN am Kabelbaum oder OBD2-Buchse anschliessen und "Verbinden" Button im Programm klicken, schon sieht man was auf dem Bus los ist.

Viele Grüsse, Rainer