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: Evaporator temperature sensor inspection
1. Turn the AUTO switch on.
2. Set the temperature control at MAX COLD (Turn the left).
3. Turn the A/C switch.
4. Set the RECIRCULATE mode.
5. Close all doors and windows.
6. Wait for 5 minutes.
7. Remove the glove compartment.
8. Disconnect the evaporator temperature sensor.
9. Measure t ...
Mazda 6 Service Manual: Variable tumble control system (vtcs) shutter valve actuator inspection
1. Remove the air hose. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION.)
2. Disconnect the vacuum hose from the VTCS shutter valve actuator.
3. Connect a vacuum pump to the VTCS shutter valve actuator.
4. Apply vacuum and verify that the rod moves.
If the rod dose not move, replace the intake ...