CAN Bus
CAN Bus and communication network analysis — verify module communication, identify bus faults, termination issues, and network integrity. When modules can't talk, nothing works right.
CAN Bus is its own world. It takes time to get good at it. But good you must get, in this modern world.
Learn the different comm types. Practice on known good. Always consider powers, grounds, and topology.
We'll see known good here first — MS and HS CAN. Then, some broken ones, and some decoding.
Reference Waveforms
Known good CAN captures every tech should recognize. Click any image to enlarge.
✓ Known Good — HS CAN
This is a very normal CAN bus on Pico. It looks noisy, but CAN is very tolerant. Some scopes “clean this up,” but I prefer no filters.
⚠ CAN Bus Lift
Any lifting like this is bad.
What to Look For
Common CAN Bus faults and what they look like on the scope.
⚠ Broken CAN
Field notes coming soon.
CAN Decoding
Reading and interpreting CAN data — turning waveforms into answers.
🔍 Decoding Examples
Field notes coming soon.
Have a good CAN capture? Send yours in.
Waveform Gallery
CAN Bus captures from the field. Text and analysis coming — images first.
OBD2 Connector — DLC Data Link 16 Pin
Field notes coming soon.
CAN Comm Failure Detail B
Field notes coming soon.
CAN Comm Failure Detail A
Field notes coming soon.
CAN Bus Comm Study
Field notes coming soon.
CAN Network Decoded
Field notes coming soon.
Mercedes CAN — HS Green
Field notes coming soon.
CAN C Topology
Field notes coming soon.
📚 More CAN captures coming — check back often
Have a waveform to contribute? Send it in
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