Diagnostic procedure
Mazda 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: Hill Launch Assist (HLA)
Hill Launch Assist (HLA) is a function which assists the driver in accelerating
from a stop while on a slope. When the driver releases the brake pedal and depresses
the accelerator pedal while on a slope, the function prevents the vehicle from rolling.
The braking force is maintained automatic ...