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: Locking, Unlocking the Doors
NOTE
The system may not operate if you are too close to the windows or door
handles.
If the key is left in the following areas and you leave the vehicle,
the doors may be locked depending on the radio wave conditions even if the key
is left in the vehicle.
Around the dashboard
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Mazda 6 Service Manual: Engine coolant temperature (ect) sensor inspection
Note
Perform the following inspection only when directed.
ECT Sensor Resistance Inspection
1. Drain the engine coolant. (See COOLING SYSTEM SERVICE WARNINGS.)
2. Remove the ECT sensor (located above the starter).
3. Place the ECT sensor in water with a thermometer, and heat the water
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