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: Operational Range
The system operates only when the driver is in the vehicle or within operational
range while the key is being carried.
Starting the Engine
NOTE
Starting the engine may be possible even if the key is outside of the
vehicle and extremely close to a door and window, however, always start the ...
Mazda 6 Service Manual: Blind Spot Monitoring (BSM) (Some models)
The Blind Spot Monitoring (BSM) is designed to assist the driver in checking
the area to the rear of the vehicle on both sides during lane changes by notifying
the driver of the presence of vehicles approaching from the rear in an adjacent
lane.
The Blind Spot Monitoring (BSM) detects vehicle ...