
Diagnostic Procedure

Dtc 18
Dtc 21Mazda 6 Service Manual: Heater core inspection
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.
If any problems are found, replace the heater core.
4. Inspect for bent fins.
If any are bent, use a flathead screwdriver to stra ...
Mazda 6 Service Manual: i-ELOOP
i-ELOOP is a regenerative braking system. When you depress the brake pedal or
use engine braking, the kinetic energy that occurs is converted to electrical energy
by the power generator and the converted electrical energy is stored in the rechargeable
battery (capacitor and battery). The store ...