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.
Mazda 6 Service Manual: Instrument cluster inspection
Speedometer
Using the input/output check mode
Inspect the speedometer by setting it in the input/output check mode DTC 12.
Using a speedometer tester
1. Adjust the tire air pressure to the specification.
2. Using a speedometer tester, verify that the speedometer indication is
within the allow ...
Mazda 6 Service Manual: Idle air control (iac) valve inspection
Note
Perform the following inspection only when directed.
Operation Test
Carry out the Idle Air Control Inspection. (See Idle Air Control System
Inspection.)
If not as specified, perform the further inspection for the IAC valve.
Resistance Inspection
1. Disconnect the negative batt ...