1. Disconnect the negative battery cable.
2. Remove the headliner.
3. Disconnect the connector.
4. Remove the screws, and then remove the sunroof motor.

Sunroof unit disassembly/assembly
Sunroof motor installationMazda 6 Service Manual: Dtc c1955, c1956
Caution
When attaching the tester lead to the DSC HU/CM connector the SST
(49 G066 004) must be used.
Diagnostic procedure
...
Mazda 6 Service Manual: Foreword
Outline
The OBD (on-board diagnostic) test inspects the integrity and function
of the air bag system and outputs the results when requested by the specific
tests.
OBD test also:
- Provides a quick inspection of the air bag system.
- Is usually performed at the start of each diagn ...