1. Remove the A/C unit. (See A/C UNIT REMOVAL/INSTALLATION.)
2. Remove the evaporator from the A/C unit.
3. Inspect for cracks, damage, and oil leakage.
4. Inspect for bent fins.
Expansion valve removal/installation
Heater core inspectionMazda 6 Service Manual: Cargo compartment light switch inspection
1. Remove the liftgate lower trim. (See LIFTGATE LOWER TRIM
REMOVAL/INSTALLATION)
2. Disconnect the cargo compartment light switch connector.
3. Inspect for continuity between the cargo compartment light switch
terminals using an ohmmeter.
If not as specified, replace the liftgate lock.
...
Mazda 6 Service Manual: Transaxle fluid temperature (tft) sensor inspection
On-Vehicle Inspection
1. Disconnect the negative battery cable.
2. Remove the air cleaner component. (See INTAKE-AIR SYSTEM
REMOVAL/INSTALLATION.)
Caution
Water or foreign objects entering the connector can cause a poor
connection or corrosion. Be sure not to drop water or foreign object ...