1. Disconnect the negative battery cable.
2. Remove the headlight cleaner switch. (See HEADLIGHT CLEANER SWITCH REMOVAL/INSTALLATION)
3. Inspect for continuity between the headlight cleaner switch terminals using an ohmmeter.


Headlight cleaner switch removal/installationMazda 6 Service Manual: No.9 noise while operating a/c system
Diagnostic procedure
* : If there is gas leakage, air enters into the A/C system. The desiccant
within the receiver/drier absorbs the moisture from the air and becomes
saturated. If the A/C system is used in this condition, the inside of the A/C
compressor will begin to rust due to this ...
Mazda 6 Service Manual: Expansion valve removal/installation
1. Disconnect the negative battery cable.
2. Discharge the refrigerant from the system. (See RECOVERY.) (See CHARGING.)
Caution
If moisture or foreign material enters the refrigeration cycle,
cooling ability will be lowered and abnormal noise will occur. Always
immediately plug open fitt ...