Front
Operational Check (Front)The purpose of the operational check is to confirm that the system operates properly.
Conditions: Engine running and at normal operating temperature
CHECKING MEMORY FUNCTION
1. Set the temperature to 90 °F or 32 °C.
2. Turn front blower control dial counterclockwise until system shuts OFF.
3. Turn ignition switch OFF.
4. Turn ignition switch ON.
5. Press the AUTO switch.
6. Confirm that the set temperature remains at previous temperature.
7. Turn front blower control counterclockwise until system shuts OFF.
If NG, go to trouble diagnosis procedure for ATC-135, "Memory Function".
If OK, continue with next check. Memory Function
CHECKING BLOWER
1. Turn front blower control clockwise, blower should operate on low speed. The blower symbol should have one blade lit (on display).
2. Turn the front blower control dial again, and continue checking blower speed and blower symbol until all speeds are checked.
3. Leave blower on MAX speed.
If NG, go to trouble diagnosis procedure for ATC-95, "DIAGNOSTIC PROCEDURE FOR BLOWER MOTOR". Front Blower Motor Circuit
If OK, continue with next check.
CHECKING DISCHARGE AIR
Mode door position is checked in the next step.
If NG, go to trouble diagnosis procedure for ATC-62, "Mode Door Motor Circuit". Mode Door Motor Circuit
If OK, continue the check.
NOTE:
Confirm that the compressor clutch is engaged (sound or visual inspection) and intake door position is at fresh when the DEF or D/F is selected.
CHECKING RECIRCULATION (, ONLY)
CHECKING TEMPERATURE DECREASE
1. Rotate temperature control dial (driver side or passenger side) counterclockwise until 16 °C (60°C). is displayed.
2. Check for cold air at appropriate discharge air outlets.
If NG, listen for sound of air mix door motor operation. If OK, go to trouble diagnosis procedure for ATC-121, "Insufficient Cooling". Insufficient Cooling If air mix door motor appears to be malfunctioning, go to ATC-72, "DIAGNOSTIC PROCEDURE FOR AIR MIX DOOR MOTOR (DRIVER)" or ATC-76, "DIAGNOSTIC PROCEDURE FOR AIR MIX DOOR MOTOR (PASSENGER)". Air Mix Door Motor Circuit
If OK, continue the check.
CHECKING TEMPERATURE INCREASE
1. Rotate temperature control dial clockwise (driver side or passenger side) until 32°C (90°F) is displayed.
2. Check for hot air at appropriate discharge air outlets.
If NG, listen for sound of air mix door motor operation. If OK, go to trouble diagnosis procedure for ATC-129, "Insufficient Heating". Insufficient Heating If air mix door motor appears to be malfunctioning, go to ATC-72, "DIAGNOSTIC PROCEDURE FOR AIR MIX DOOR MOTOR (DRIVER)" or ATC-76, "DIAGNOSTIC PROCEDURE FOR AIR MIX DOOR MOTOR (PASSENGER)". Air Mix Door Motor Circuit
If OK, continue with next check.
CHECK A/C SWITCH
1. Press A/C switch when AUTO switch is ON, or in manual mode.
2. A/C switch indicator will turn ON.
- Confirm that the compressor clutch engages (sound or visual inspection).
NOTE:
If current mode setting is DEF or D/F, compressor clutch may already be engaged.
If NG, go to trouble diagnosis procedure for ATC-115, "Magnet Clutch Circuit". Magnet Clutch Circuit
If OK, continue with next check.
CHECKING AUTO MODE
1. Press AUTO switch.
2. Display should indicate AUTO.
- If ambient temperature is warm, and selected temperature is cool, confirm that the compressor clutch engages (sound or visual inspection). (Discharge air and blower speed will depend on ambient, in-vehicle, and set temperatures.)
If NG, go to trouble diagnosis procedure for ATC-59, "Power Supply and Ground Circuit for Front Air Control", Power Supply and Ground Circuit For Front Air Control then if necessary, trouble diagnosis procedure for ATC-115, "Magnet Clutch Circuit". Magnet Clutch Circuit
If all operational checks are OK (symptom cannot be duplicated), go to malfunction Simulation Tests in ATC-36, "How to Perform Trouble Diagnosis for Quick and Accurate Repair" and perform tests as outlined to simulate driving conditions environment. Work Flow If symptom appears. Refer to ATC-36, "How to Perform Trouble Diagnosis for Quick and Accurate Repair", Work Flow ATC-36, "SYMPTOM TABLE" and perform applicable trouble diagnosis procedures. Symptom Matrix Chart