A session is one recording at one truck. It is what every report, every comparison and every timeline entry is built from, so it is worth getting the first one right.
Key on, connect, and watch the live line at the bottom of the window — engine speed, load, coolant, oil pressure updating every second. If that line is not moving, stop and fix it before recording; a silent recording is worth nothing.
Rignos reads VIN and engine serial off the bus where the ECM publishes them. Fill in anything missing — the truck record in your workspace is matched on these.
Follow the on-screen script if your shop has one loaded. A useful baseline is a settled idle, then a load pull, then back to idle. Sixty seconds is enough for a snapshot, but a pull needs actual load — an idling engine cannot tell you about power.
The app writes the session out immediately: per-second values, a summary with min/mean/max, the identity block, active fault codes, and the raw frames. It also flags any value that falls outside physical range, which is your first hint that a sensor — not the engine — is the problem.
Back on shop Wi-Fi, the session uploads to your workspace. Recordings queue on disk while you are offline and go up when the connection returns; you do not have to wait at the truck.
One session row under the truck, on that truck’s timeline, with the tech and machine that produced it recorded. From there you can open it, compare it against the previous visit, and hand it to the customer.