
Diagnostic procedure

Dtc p0420
Dtc p0480Mazda 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: Intermittent concern troubleshooting
Vibration Method
If malfunction occurs or becomes worse while driving on a rough road or
when engine is vibrating, perform the steps below.
Note
There are several reasons why vehicle or engine vibration could
cause an electrical malfunction. Some of the things to check for:
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