Inspection Flow
- CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - TEMPERATURE INCREASE
- Press the AUTO switch.
- Turn the temperature control dial (driver) clockwise until 32° C (90° F) is displayed.
- Check for hot air at discharge air outlets.
Can this symptom be duplicated?
Yes: GO TO 2.
NO: Perform complete system operational check. Refer to "OPERATIONAL CHECK ".
- CHECK FOR SERVICE BULLETINS
Check for any service bulletins.
: GO TO 3.
- PERFORM FRONT AIR CONTROL SELF-DIAGNOSIS
Perform front air control self-diagnosis. Refer to "FRONT AIR CONTROL SELF - DIAGNOSIS ".
OK or NG
OK: GO TO 4.
NG: Perform power and ground circuit for front air control. Refer to "POWER SUPPLY AND GROUND CIRCUIT FOR FRONT AIR CONTROL AND UNIFIED METER AND A/C AMP .".
- PERFORM SELF-DIAGNOSIS STEP - 2
Perform self-diagnosis STEP - 2. Refer to "FUNCTION CONFIRMATION PROCEDURE ".
OK or NG
OK: GO TO 5.
NG: Perform appropriate malfunctioning sensor circuit.
- PERFORM SELF-DIAGNOSIS STEP - 4
Perform self-diagnosis STEP - 4. Refer to "FUNCTION CONFIRMATION PROCEDURE ".
OK and NG
OK: GO TO 6.
NG:
- Check LAN system circuit. Refer to "LAN SYSTEM CIRCUIT ".
- Check blower motor circuit. Refer to "BLOWER MOTOR CIRCUIT ".
- CHECK ENGINE COOLING SYSTEM
- Check for proper engine coolant level. Refer to "CHECKING RESERVOIR LEVEL ".
- Check hoses for leaks or kinks.
- Check radiator cap. Refer to "CHECKING RADIATOR CAP ".
- Check for air in cooling system.
OK or NG
OK: GO TO 7.
NG: Repair as necessary.
- CHECK AIR MIX DOOR OPERATION
Check the operation of the air mix door.
OK or NG
OK: GO TO 8.
NG: Check the air mix door motor circuit. Refer to "AIR MIX DOOR MOTOR CIRCUIT ".
- CHECK AIR DUCTS
Check for disconnected or leaking air ducts.
OK or NG
OK: GO TO 9.
NG: Repair all disconnected or leaking air ducts.
- CHECK HEATER HOSE TEMPERATURES
- Start engine and warm it up to normal operating temperature.
- Touch both the inlet and outlet heater hoses.
OK or NG
OK: Hot inlet hose and a warm outlet hose: GO TO 10.
NG: Both hoses warm: GO TO 11.
- CHECK ENGINE COOLANT SYSTEM
Check engine control temperature sensor. Refer to "DTC P0117, P0118 ECT SENSOR .
OK or NG
OK: System OK.
NG: Repair or replace as necessary. Retest.
- CHECK HEATER HOSES
Check heater hoses for proper installation.
OK or NG
OK: System OK.
NG:
- Back flush heater core.
- Drain the water from the system.
- Refill system with new engine coolant. Refer to "CHANGING ENGINE COOLANT ".
- GO TO 12 to retest.
- CHECK HEATER HOSE TEMPERATURES
- Start engine and warm it up to normal operating temperature.
- Touch both the inlet and outlet heater hoses.
OK or NG
OK: System OK.
NG: Replace heater core. Refer to "HEATER CORE ".