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: Front door speaker removal/installation
1. Disconnect the negative battery cable.
2. Remove the front door trim.
3. Remove in the order indicated in the table.
4. Install in the reverse order of removal.
Front Door Speaker Installation Note
Attach the speaker with the wiring harness placed in the groove of the door
unit panel.
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Mazda 6 Service Manual: Solenoid valve removal/installation
1. Disconnect the negative battery cable.
2. Remove the under cover.
3. Remove the control valve body. (See CONTROL VALVE BODY REMOVAL.)
4. Remove the solenoid valve(s).
5. Apply ATF to a new O-ring and install it on the solenoid valve.
6. Install the solenoid valve in the control valve body. ...