WARNING:
Never remove the cooling system cap or loosen the radiator drain plug while the engine is running, or when the engine and radiator are hot. Scalding engine coolant and steam may shoot out and cause serious injury. It may also damage the engine and cooling system.
Turn off the engine and wait until it is cool. Even then, be very careful when removing the cap. Wrap a thick cloth around it and slowly turn it counterclockwise 2.5 turns. Step back while the pressure escapes.
When you are sure all the pressure is gone, turn the cap using the cloth, and remove it.
1. Inspect the engine coolant level..
2. Remove the cooling system cap.
3. Install the SST
or aftermarket equivalent and a radiator cap tester to the coolant reserve tank filler port.

4. Apply pressure using the radiator cap tester.
CAUTION:
Applying more than 155 kPa {1.58 kgf/cm2, 22.5 psi} can damage the hoses, fittings, and other components, and cause leakage.
155 kPa {1.58 kgf/cm2, 22.5 psi} [1 min]
5. When pressurizing the cooling system, verify that the pressure is maintained.
If the gauge needle drops, it may indicate water leakage. Repair or replace the applicable part.
Cooling System Service Warnings [Mzr 2.0, Mzr 2.5]
Engine Coolant Level Inspection [Mzr 2.0, Mzr 2.5]Variable Swirl Solenoid Valve Inspection [Mzr 2.3 Disi Turbo]
Airflow Inspection
1. Remove the battery cover..
2. Disconnect the negative battery cable..
3. Remove the variable swirl solenoid valve..
4. Inspect the airflow between the ports under the following conditions.
If not as specified, replace the variable swirl solenoid valve..
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Manual Transaxle Removal/Installation [G35 M R]
CAUTION:
Secure the steering wheel using tape or a cable to prevent the steering shaft
from rotating after disconnecting the steering shaft. If the steering wheel
rotates after the steering shaft and the steering gear and linkage are disconnected,
the internal parts of the clock spr ...
Stop Vehicle in Safe Place Immediately
If any of the following warning lights turns on, the system may have a
malfunction. Stop the
vehicle in a safe place immediately and contact an Authorized Mazda Dealer.
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