Power Supply And Ground Circuit For Controller

POWER SUPPLY AND GROUND CIRCUIT FOR CONTROLLER

Component 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, defroster door motor, blower motor and compressor are then controlled.
The front air control is unitized with control mechanisms. When the various switches and temperature dials are operated, data is input to the front air control.
Self-diagnostic functions are also built into the front air control to provide quick check of malfunctions in the auto air conditioner system.
Potentio Temperature Control (PTC)





There are two PTCs (driver and passenger) built into the front air control. They can be set at an interval of 0.5�
C (1.0�F) in the 18�C
(60�F) to 32�C (90�F) temperature range by rotating the temperature dial. The set temperature is displayed.


Front Air Control Component Function Check

SYMPTOM: A/C system does not come on.

INSPECTION FLOW


1. CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - AUTO MODE

1.Press AUTO switch.
2.Confirm that the compressor clutch engages (sound or visual inspection). (Discharge air and blower speed will depend on ambient, in-vehicle and set temperatures.)
Is the inspection result normal?
YES- Inspection End.
NO- Go to diagnosis procedure. .


Front Air Control Power and Ground Diagnosis Procedure

Regarding Wiring Diagram information, Automatic Air Conditioning.

DIAGNOSTIC PROCEDURE FOR A/C SYSTEM






SYMPTOM: A/C system does not come on.

1. CHECK POWER SUPPLY CIRCUITS FOR FRONT AIR CONTROL






1.Turn ignition switch ON.
2.Check voltage between front air control harness connector M49
(B) terminal 15 and M50 (A) terminal 27, and ground.





Is the inspection result normal?
YES- GO TO 2.
NO-Check 10A fuses [Nos. 8 and 19, located in the fuse block (J/B)]. Fuse, Fusible Link And Relay Box.
- If fuses are OK, check harness for open circuit. Repair or replace as necessary.
- If fuses are NG, replace fuse and check harness for short circuit. Repair or replace as necessary.

2. CHECK GROUND CIRCUIT FOR FRONT AIR CONTROL






1.Turn ignition switch OFF.
2.Disconnect front air control connectors.
3.Check continuity between front air control harness connector
M50 terminal 35 and ground.
35 - Ground: Continuity should exist.
Is the inspection result normal?
OK- Replace front air control. Service and Repair.
NG- Repair harness or connector.