
Diagnostic procedure

Dtc b1231
Dtc b1869, b1870Mazda 6 Service Manual: Electrical parts
Battery cable
Before disconnecting connectors or removing electrical parts, disconnect
the negative battery cable.
Wiring Harness
To remove the wiring harness from the clip in the
engine room, pry up the hook of the clip using a
flathead screwdriver.
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Mazda 6 Service Manual: Headlights
Turn the headlight switch to turn the headlights and other exterior lights on
or off. When the lights are turned on, the lights-on indicator light in the instrument
cluster turns on.
NOTE
If the light switch is left on, the lights will automatically switch
off approximately 30 seconds ...