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: Inspection of dtcs for condition detection mode
Note
The cruise set indicator light will illuminate for 3 seconds,
when condition detection mode is on.
If the RESUME/ACCEL switch on the cruise control switch is
malfunctioning, the cruise set indicator light will not give a correct
indication when you inspect the system.
1. Drive ...
Mazda 6 Service Manual: Instrument cluster inspection
Speedometer
Using the input/output check mode
Inspect the speedometer by setting it in the input/output check mode DTC 12.
Using a speedometer tester
1. Adjust the tire air pressure to the specification.
2. Using a speedometer tester, verify that the speedometer indication is
within the allow ...