Upshifting
For normal acceleration and cruising, Mazda recommends these shift points:

*1 Always observe local speed limit regulations.
Downshifting
When you must slow down in heavy traffic or on a steep upgrade, downshift before the engine starts to overwork. This gives better acceleration when you need more speed.
On a steep downgrade, downshifting helps maintain safe speed and prolongs brake life.
Shift Gear (Shifting) Speed Limit
Direct ModeMazda 6 Owners Manual: System wiring diagram
ABS (ABS/TCS)
DSC
FOREWORD
Before performing the steps in Symptom Troubleshooting, perform the
On-board Diagnostic Inspection. To check the DTC, follow the DTC Inspection
steps.
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Mazda 6 Owners Manual: Emergency Locking Mode
When the seat belt is fastened, it will always be in the emergency locking mode. In the emergency locking mode, the belt remains comfortable on the occupant and the retractor will lock in position during a collision.
If the belt is locked and cannot be pulled out, retract the belt once, and then ...