1. Disconnect the back-up light switch connector.
2. Inspect for continuity between the back-up light switch terminals using an ohmmeter.


Back-up light switch removal/installation
Flasher unit removal/installationMazda 6 Service Manual: Exterior lighting system
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Mazda 6 Service Manual: Power brake unit removal/installation
1. Remove the master cylinder. (See MASTER CYLINDER REMOVAL/INSTALLATION.)
2. Remove the wiper arm. (See WINDSHIELD WIPER ARM AND BLADE
REMOVAL/INSTALLATION.)
3. Remove the cowl grille. (See COWL GRILLE REMOVAL/INSTALLATION.)
4. Remove the wiper motor. (See WINDSHIELD WIPER MOTOR REMOVAL/INSTAL ...