Operational Check

TROUBLE DIAGNOSIS


Operational Check

The purpose of the operational check is to confirm that the system operates properly.

Conditions : Engine running at normal operating temperature

CHECKING BLOWER
1. Turn blower control dial clockwise, blower should operate on low speed.
2. Continue turning blower control dial clockwise, and continue checking blower speeds until all speeds are checked.
3. Leave blower on Maximum speed.
If NG, go to Blower Motor Circuit.
If OK, continue the check.

CHECKING DISCHARGE AIR
1. Turn mode door control dial to each position.
2. Confirm that discharge air comes out according to the air distribution table. Discharge Air Flow.






NOTE:
Confirm that the compressor clutch is engaged (audio or visual inspection) and intake door is in the fresh
( ) position when the DEF is selected.
Intake door position is checked in the next step.
If NG, go to Mode Door Motor Circuit, Mode Door Motor.
If OK, continue the check.

CHECKING RECIRCULATION






1. Press REC switch.
Recirculation indicator should illuminate.
2. Press REC switch a second time.
Recirculation indicator should turn off.
3. Listen for intake door position change (you should hear blower sound change slightly).
If NG, go to Intake Door Motor Circuit.
If OK, continue with the check.

CHECKING TEMPERATURE DECREASE
1. Turn temperature control dial counterclockwise to full cold position.
2. Check for cold air at discharge air outlets.
If NG, go to Insufficient Cooling.
If OK, continue the check.

CHECKING TEMPERATURE INCREASE
1. Turn temperature control dial clockwise to full hot position.
2. Check for hot air at discharge air outlets.
If NG, go to Insufficient Heating.
If OK, continue the check.

CHECKING A/C SWITCH (IF EQUIPPED)
1. Turn blower control dial to the desired position and push the air conditioner switch (if equipped) to turn ON the air conditioner.
2. Confirm that the A/C indicator lamp illuminates and that the compressor clutch engages (audio or visual inspection).
If NG, go to Power Supply And Ground Circuit For Front Air Control, then if necessary, Magnet Clutch Circuit (If Equipped).
If all operational checks are OK (symptom can not be duplicated), go to How to Perform Efficient Diagnosis for an Electrical Incident and perform tests as outlined to simulate driving condition environment. If symptom appears, How To Perform Trouble Diagnosis For Quick And Accurate Repair and perform applicable trouble diagnosis procedures.