When emission-related ECU detects a malfunction in the emission control systems components and/or the powertrain control components (which affect vehicle emissions), it turns on/blinks MIL to inform the driver that a malfunction has been detected.
NOTE:
Check the MIL circuit if MIL does not illuminate. Refer to EC- 467, "Component Function Check".

NOTE:
If MIL continues to illuminate/blink, perform self-diagnoses and inspect/repair accordingly because an emission-related ECU has detected a malfunction in the emission control systems components and/or the powertrain control components (which affect vehicle emissions).
Diagnosis description : permanent diagnostic
trouble code (permanent DTC)
On board diagnosis functionSymptom diagnosis
HEATER AND AIR CONDITIONING SYSTEM
CONTROL SYMPTOMS
Symptom Table
INSUFFICIENT COOLING
Component Function Check
Symptom: insufficient cooling
Inspection flow
1. Confirm symptom by performing operation check - temperature decrease
Press the a/c switch.
Turn temperature control dial c ...
Passenger compartment
CAUTION
Never use a fuse of a higher or lower
amperage rating than specified on the
fuse box cover. This could damage the
electrical system or cause a fire.
If any electrical equipment does not operate,
check for an open fuse.
NOTE:
The fuse box is located on the driver’s side
of the ...
Hvac branch line circuit
Diagnosis procedure
1.Check connector
Turn the ignition switch off.
Disconnect the battery cable from the negative terminal.
Check the terminals and connectors of the a/c auto amp. For damage, bend
and loose connection (unit
side and connector side).
Is the inspection result normal? ...