1. Connect the WDS or equivalent to the DLC-2.
2. Measure the PID value.
Note
PID/DATA MONITOR AND RECORD function table

Dtc p0841
TroubleshootingMazda 6 Service Manual: Viewing the Display
Guide lines which indicate the width of the vehicle (yellow) are displayed on
the screen as a reference to the approximate width of the vehicle in comparison
to the width of the parking space you are about to back into.
Use this display view for parking your vehicle in a parking space or garage ...
Mazda 6 Service Manual: Distance Recognition Support System (DRSS) (Some models)
The Distance Recognition Support System (DRSS) measures the distance between
your vehicle and a vehicle ahead using a radar sensor (front) while the vehicle
speed is about 30 km/h (19 mph) or faster, and if your vehicle approaches a vehicle
ahead more closely than what is appropriate for maint ...