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: Dual proportioning valve replacement (without abs)
1. Remove in the order indicated in the table.
2. Install in the reverse order of removal.
Dual Proportioning Valve Installation Note
Install the dual proportioning valve so that the R mark faces the left side
of the vehicle.
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Mazda 6 Service Manual: Rear bumper removal/installation
1. Disconnect the negative battery cable.
2. Remove the rear combination light.
3. Remove in the order indicated in the table.
4. Install in the reverse order of removal.
Rear Bumper Removal Note
Pull the rear bumper ends (wheel arch) outward to disengage with the bumper
slider.
Cautio ...