Bottle holders are on the inside of the doors.

CAUTION
Do not use the bottle holders for containers without caps. The contents may spill when the door is opened or closed.
Cup Holder
Storage CompartmentsMazda 6 Owners Manual: Service procedure
Inspection, adjustment
Inspection and adjustment procedures are divided into steps. Important
points regarding the location and contents of the procedures are explained
in detail and shown in the illustrations.
Repair procedure
1. Most repair operations begin with an overview illustr ...
Mazda 6 Owners Manual: Rear door speaker inspection
1. Inspect for resistance between the rear door speaker terminals using an
ohmmeter.
If not as specified, replace the rear door speaker.
2. To verify that the rear door speaker outputs sound, apply voltage to the
rear door speaker and release using a 1.5-V battery.
If not outputs ...