The tachometer shows engine speed in thousands of revolutions per minute (rpm).
CAUTION
Do not run the engine with the tachometer needle in the RED ZONE. This may cause severe engine damage.

NOTE
When the tachometer needle enters the STRIPED ZONE, this indicates to the driver that the gears should be shifted before entering the RED ZONE.
Speedometer, Odometer, Trip Meter and Trip Meter Selector (Without Multiinformation
Display)
Engine Coolant Temperature Gauge (Without Multi-information Display)Mazda 6 Owners Manual: Discharge headlight service warnings
Discharge headlight bulb service warnings
To prevent electrical shock when replacing the discharge headlight bulb,
dry hands thoroughly, and carry out work in an area out of rain.
When the light switch is on, approx. 25,000 V of high voltage passes
through the discharge headlight bulb so ...
Mazda 6 Owners Manual: Dual proportioning valve replacement (without abs)
1. Remove in the order indicated in the table.
2. Install in the reverse order of removal.
Dual Proportioning Valve Installation Note
Install the dual proportioning valve so that the R mark faces the left side
of the vehicle.
...