1. Remove the A/C unit. (See A/C UNIT REMOVAL/INSTALLATION.)
2. Remove the heater core from the A/C unit.
3. Inspect for cracks, damage, and coolant leakage.
4. Inspect for bent fins.
5. Verify that the heater core inlet and outlet pipe are not distorted or damaged.
Evaporator inspection
Rear heat duct removal/installationMazda 6 Service Manual: Engine coolant temperature (ect) sensor removal/installation
Warning
When the engine is hot, it can badly burn. Turn off the engine and
wait until it is cool before removing the ECT sensor.
1. Drain the engine coolant. (See COOLING SYSTEM SERVICE WARNINGS.)
2. Disconnect the ECT sensor connector.
3. Remove the ECT sensor.
4. Install in the reve ...
Mazda 6 Service Manual: No.5 tcs off light does not illuminate with ignition switch on
Diagnostic procedure
When performing an asterisked (*) troubleshooting inspection, shake the
wiring harness and connectors while doing the inspection to discover whether
poor contact points are the cause of any intermittent malfunction. If there
is a problem, check to make sure co ...