Scan data
What freeze-frame data tells you
A freeze frame is a snapshot of some operating data captured near a fault event. Read it before erasing codes.
Capture the details
Save the associated code and the fields your reader provides. Engine speed, coolant temperature, vehicle speed and calculated load can help you tell a cold idle from a warm uphill pull. Available fields vary.
Use it to ask a better question
Say a lean code appeared at warm idle. That gives the technician a specific operating condition to compare with live fuel-trim data. A code set at higher load would point to a different comparison.
Keep the original values
Export or photograph the screen with the units visible. Freeze-frame availability and which event gets saved depend on the vehicle and tool. Keep live data readings in a separate note.