Automatic Air Conditioning

POWER SUPPLY AND GROUND CIRCUIT FOR FRONT AIR CONTROL

Description


COMPONENT DESCRIPTION

FRONT AIR CONTROL





The front air control has a built-in microcomputer which processes information sent from various sensors needed for air conditioner operation. The air mix door motors, mode door motor, intake door motor, blower motor and compressor are then controlled.
Signals from various switches and Potentio Temperature Control (PTC) are directly entered into front air control.
POTENTIO TEMPERATURE CONTROL (PTC)
The PTC is built into the front air control.


Component Function Check


COMPONENT INSPECTION

SYMPTOM: A/C system does not come on.
INSPECTION FLOW

1. CONFIRM SYMPTOM BY PERFORMING OPERATION CHECK - AUTO MODE

1.Press AUTO switch (indicator should illuminate).
2.Confirm that the compressor clutch engages (sound or visual inspection). (Discharge air and blower speed will depend on ambient, in-vehicle and set temperature.)
Is the inspection result normal?
YES- Inspection End.
NO- Go to diagnosis procedure for Power and Ground Circuit for Front Air Control. Refer to "Diagnosis Procedure".


Diagnosis Procedure

Regarding Wiring Diagram information, Coupe or Sedan.

DIAGNOSIS PROCEDURE FOR A/C SYSTEM






SYMPTOM: A/C system does not come on.

1. CHECK POWER SUPPLY CIRCUIT FOR FRONT AIR CONTROL






1.Disconnect front air control connector M152.
2.Press ignition switch ON.
3.Check voltage between front air control connector M152 terminals 19, 39 and 40, and ground.





Is the inspection result normal?
YES- GO TO 2
NO-Check the following.
- 10A fuses [Nos. 6, 19, and 3, located in the fuse block (J/B)].
- If fuses are OK, check for open circuit in wiring harness. Repair or replace as necessary.
- If fuses are NG, replace fuse and check wiring harness for short circuit. Repair or replace as necessary.

2. CHECK BODY GROUND CIRCUIT FOR FRONT AIR CONTROL






1.Press ignition switch OFF.
2.Check continuity between front air control connector M152 terminals 17 and 37 and ground.





Is the inspection result normal?
YES- - Replace front air control. Service and Repair.
- Inspection End.
NO- Repair or replace harness.