WARNING
Always check that the hood is closed and securely locked:
A hood that is not closed and securely locked is dangerous as it could fly open while the vehicle is moving and block the driver's vision which could result in a serious accident.
Owner Maintenance Precautions
Opening the HoodMazda 6 Owners Manual: Thermostat
THERMOSTAT REMOVAL/INSTALLATION
1. Remove the plug hole plate.
2. Disconnect the negative battery cable.
3. Drain the engine coolant. (See COOLING SYSTEM SERVICE WARNINGS.)
4. Remove the drive belt. (See DRIVE BELT REPLACEMENT.)
5. Remove the washer tank.
6. Remove the P/S oil pump.
Note
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Mazda 6 Owners Manual: Service cautions
HANDLING INSUFFICIENT REFRIGERANT LEVEL
If an insufficient refrigerant level is detected at troubleshooting,
do not charge (add) the refrigerant. Because an accurate amount of
refrigerant cannot be determined from the pressure indicated on the manifold
gauge, never charge the refrigeran ...