1. Disconnect the negative battery cable..
2. Remove the rear door trim..
3. Remove the rear door speaker..
4. Verify the resistance between the rear door speaker terminals.

If not within the specification, replace the rear door speaker.

Without Bose®: 3.4—4.6 ohms
With Bose®: 2.89—3.91 ohms
Rear Center Speaker Removal/Installation
Rear Door Speaker Removal/InstallationSpark Plug Inspection [Skyactiv G 2.0]
Specification
Spark plug type
PE01-18110, PE02-18110, PE5R-18110, PE5S-18110
Plug Gap Inspection
CAUTION:
To avoid possible damage to the tip, do not adjust the plug gap.
To prevent damaging the tip, use a wire type plug gap gauge when inspecting
the plug gap.
...
Battery Inspection [Mzr 2.0, Mzr 2.5]
WARNING:
Since battery acid is toxic, be careful when handling the battery.
Since battery acid is highly corrosive, be careful not to allow it to contact
clothing or the vehicle.
In case battery acid contacts skin, eyes, or clothing, flush it immediately
with running wa ...
Fuel Line Pressure Inspection [Skyactiv G 2.0]
WARNING:
Fuel line spills and leakage from the pressurized fuel system are dangerous.
Fuel can ignite and cause serious injury or death and damage. To prevent this,
complete the following inspection with the engine stopped.
Fuel is very flammable liquid. If fuel spills or leaks ...