Mazda 6 Service Manual: Dtc b1921
Diagnostic procedure
Dtc b1913, b1925, b1933, b1935
Diagnostic procedure
...
Dtc b1992, b1993, b1994, b1995
Diagnostic procedure
...
Other materials:
Mazda 6 Service Manual: Sas unit configuration
1. Connect the SST (WDS or equivalent) to the DLC-2.
2. Input vehicle information following the directions on the screen.
3. Select Module programming.
4. Select Programmable module installation.
5. Select the following items and perform procedures according to directions
on the screen.
...
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 ...