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SavvyCAN Quick Start

Quick start for the DauntlessOBD device and our CAN Interface board, for using SavvyCAN via a USB connection. If you wish to use serial terminal commands, please see DauntlessOBD Developer & API Info.

SavvyCAN is a great open source project for monitoring and reverse engineering CAN traffic on Windows, Mac, and Linux. We are not affiliated with this project, just a huge fan, and we’ve added support for it to our products. The current SavvyCAN release can be obtained on GitHub.

Please note that if you are connected to the vehicle’s OBD port, or the OBD CAN wires, many recent vehicles will not have CAN broadcast traffic visible here, due to their use of a gateway device. As such, you may only see the CAN traffic to/from other OBD devices that are plugged in, which is useful for inspecting what they are doing, but you may not see anything unless said device is actively talking. To get more interesting CAN data on these newer vehicles, users typically connect a CAN Interface to the wires of a different CAN bus on the other side of the gateway.

Many mid-2000’s to mid-2010’s vehicles, most notably excluding VW/Audi/Porsche, will however have CAN broadcast traffic visible via the OBD port, so it’s usually still worth giving that a try first because it’s the easiest option.

SavvyCAN Quick Start for DauntlessOBD and CAN Interface

Connect your device to the vehicle’s OBD port (DauntlessOBD) or CAN wires (CAN Interface). If connecting directly to CAN wiring, be sure to use appropriate connectors and procedures, as well as setting the correct CAN termination jumpers, to avoid causing bus faults or damage.

Connect your device to your computer via a USB-C cable.

Start the SavvyCAN program.

Navigate the menu to Connection -> “Open Connection Window”.

Click the “Add New Device Connection” button.

Select “Serial Connection (GVRET)”, then set the Serial Port to the port your device is on.

Windows: it will be a COMx: port, and you can tell which one by opening Device Manager and going to Ports “(COM & LPT)”, then looking for “USB Serial Device”.

macOS: it will typically be /dev/tty.usbmodemXXXX

Linux: it will typically be /dev/ttyACM0 (Ubuntu and others; make sure your user account has permission to access it)

Click “Create New Connection”.

It should now appear in the list. Wait for it to show “Connected” status, and then double-click on it to view and change the Bus Details.

IMPORTANT: The Bus Details section may not be correct unless you first double-clicked on the device in the list.

In the Bus Details section at the bottom, you can choose the CAN Bus Speed, Listen Only Mode, and Enable.

A speed of 500000 is typical for OBD-II CAN, 250000 or 125000 for many comfort or body CANs, 33333 for General Motors Single-Wire CAN (aka GMLAN). We recommend using “Listen Only” mode to avoid disrupting the bus in case you have the Speed set incorrectly.

Click “Save Bus Settings” when done.

Exit the “Connection Settings” window. Any CAN traffic should be appearing on the main screen, assuming that there is traffic and the CAN bus speed is set correctly.

If the USB cable gets disconnected or the the connection is otherwise interrupted, you’ll need to return to the Connection Settings window to reestablish it.