Connect battery positive voltage to terminal A and ground to terminal B of the blower motor and verify its operation.

Blower motor removal/installation
Resistor removal/installationMazda 6 Service Manual: Foreword
When the customer reports a vehicle malfunction, check the malfunction
indicator lamp (MIL), HOLD indicator light flashing, and PCM memory for
diagnostic trouble code (DTC), then diagnose the malfunction according to
following flowchart.
- If the DTC exists, diagnose the applicable ...
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 ...