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 c1145, c1155, c1165, c1175
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: Locking, Unlocking with Door- Lock Knob
Operation from inside
To lock any door from the inside, press the door-lock knob.
To unlock, pull it outward. This does not operate the other door locks.
NOTE
The red indication can be seen when the door-lock knob is unlocked.
Operation from outside
To lock the rear and front passenger doo ...