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 inspection (without abs)
1. Connect the SSTs to the brake pipes as shown in the figure.
2. Bleed the air from the brake system.
3. Measure the fluid pressure of the master cylinder and the rear brake.
If not within the specification, replace the dual proportioning valve.
Fluid pressure
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Mazda 6 Service Manual: Engine oil replacement
Warning
Hot engines and engine oil can cause severe burns. Turn off the
engine and wait until it and the engine oil has cooled.
A vehicle that is lifted but not securely supported on safety
stands is dangerous. It can slip or fall, causing death or serious injury.
Never work around or ...