1. Remove the sunroof switch.
2. Inspect for continuity between the sunroof switch terminals using an ohmmeter.


Sunroof switch removal/installationMazda 6 Service Manual: Overheating
If the high engine coolant temperature warning light turns on, the vehicle loses
power, or you hear a loud knocking or pinging noise, the engine is probably too
hot.
WARNING
Pull over to a safe location,
then switch the ignition off and make sure the fan is not running before attempting
t ...
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 ...