1. Remove the door switch. (See DOOR SWITCH REMOVAL/INSTALLATION)
2. Inspect for continuity between the door switch terminal and a body ground using an ohmmeter.


Door switch removal/installation
Ashtray illumination bulb removal/installationMazda 6 Service Manual: System wiring diagram
ABS (ABS/TCS)
DSC
FOREWORD
Before performing the steps in Symptom Troubleshooting, perform the
On-board Diagnostic Inspection. To check the DTC, follow the DTC Inspection
steps.
...
Mazda 6 Service Manual: Range of topics
This manual contains procedures for performing all required service
operations. The procedures are divided into the following five basic
operations:
Removal/Installation
Disassembly/Assembly
Replacement
Inspection
Adjustment
Simple operations which can be perf ...