Diagnostic Procedure
Mazda 6 Service Manual: Ignition switch inspection
1. Disconnect the negative battery cable.
2. Remove the column cover. (See COLUMN COVER REMOVAL/INSTALLATION)
3. Disconnect the ignition switch connectors.
4. Inspect for continuity between the ignition switch terminals using an
ohmmeter.
If not as specified, replace the ignition switch.
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Mazda 6 Service Manual: Procedures for determining the location of a malfunction
System Wiring Diadram
PCM
1. Check the display of DTC U0121 and/or U0155, using the SST (WDS or
equivalent). (See DTC TABLE.)
2. Referring to the following table, determine the malfunctioning part of the
CAN system.
ABS/TCS HU/CM or DSC HU/CM
1. Accec and monitor the PCM MSG and IC MSGo ...