1. Measure the temperature around the water temperature sensor.
2. Measure the resistance between terminals of the water temperature sensor.

Water temperature sensor removal/installation
Refrigerant pressure switch removal/installationMazda 6 Service Manual: Trunk side trim removal/installation
4SD
1. Remove the trunk end trim.
2. Remove the fasteners, then remove the trunk side trim.
3. Install in the reverse order of removal.
5HB
1. Remove the trunk end trim.
2. Remove the trunk side upper trim.
3. Remove the cargo hooks.
4. Remove the fasteners.
5. Pull the trunk side trim ...
Mazda 6 Service Manual: Inspecting Coolant Level
WARNING
Do not use a match or live flame in the engine compartment. DO NOT ADD
COOLANT WHEN THE ENGINE IS HOT: A hot engine is dangerous. If the engine has
been running, parts of the engine compartment can become very hot. You could be
burned. Carefully inspect the engine coolant in the coola ...