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: 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
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Mazda 6 Service Manual: Driving Tips
WARNING
Do not let the vehicle move in a direction opposite to the direction selected
by the selector lever: Do not let the vehicle move backward with the selector
lever in a forward position, or do not let the vehicle move forward with the selector
lever in the reverse position. Otherwise, t ...