Control System Description Manual A/C (Type 1)

MANUAL AIR CONDITIONER SYSTEM


Control System Description


CONTROL OPERATION
Front air control






TEMPERATURE CONTROL DIAL (TEMPERATURE CONTROL)
Increases or decreases the set temperature.




RECIRCULATION ( ) SWITCH
- When REC switch is ON, REC switch indicator turns ON, and air inlet is set to REC.
- When REC switch is turned OFF, or when compressor is turned from ON to OFF, REC switch is automatically turned OFF. REC mode can be re-entered by pressing REC switch again.
- REC switch is not operated when DEF switch is turned ON, or at the D/F or FOOT position.




DEFROSTER ( ) SWITCH
Positions the air outlet doors to the defrost position. Also positions the intake doors to the outside air position.

REAR WINDOW DEFOGGER SWITCH
When switch is ON, rear window defogger is activated.

OFF SWITCH (BLOWER SPEED DIAL)
When the blower speed dial is turned all the way counter-clockwise, the compressor and blower are OFF.

A/C SWITCH
Sends a signal to the BCM requesting the A/C compressor be turned ON or OFF.
(Pressing the A/C switch will turn off the A/C switch and compressor.)

MODE SWITCHES
Controls the air discharge outlets.

FRONT BLOWER CONTROL DIAL
Sends a fan ON signal to the BCM and manually controls the blower speed.

MAGNET CLUTCH CONTROL





In order for the IPDM E/R to complete a compressor ON request, the following conditions must be met:
- The blower speed dial is in one of the fan speed positions. This allows the front air control to send a fan ON signal to the BCM.
- The A/C switch is pressed. The A/C switch LED illuminates and the front air control outputs a compressor
ON signal to the BCM. Any mode control button may be selected.
- If the A/C switch is OFF, and the MAX A/C button is pressed, the A/C switch LED will automatically illuminate and the front air control outputs a compressor ON signal to the BCM.
- If the A/C switch is OFF, and the mode buttons for either D/F or DEF are selected, the front air control will send a compressor ON signal to the BCM, but it does not illuminate the A/C switch LED
- The intake temperature value must be within the specified range.
Once the front air control conditions are met and the fan ON and compressor ON signals are detected by the
BCM:
- The BCM sends a compressor ON signal to the ECM, via CAN communication line.
- the ECM judges whether the compressor can be turned ON, based on each sensor status (refrigerant pressure sensor signal, throttle angle sensor, etc.). If it judges compressor can be turned ON, it sends compressor ON signal to IPDM E/R, via CAN communication line.
- Upon receipt of compressor ON signal from ECM, IPDM E/R turns air conditioner relay ON to operate the compressor.

Defrost latching logic
If the compressor was engaged by pressing the D/F or DEF mode buttons, and the time spent in either mode exceeds 1 minute, then the compressor stays requested, even when modes other than D/F or DEF are selected, until either:
1. The ignition switch is turned OFF.
2. The blower speed dial is turned completely counter-clockwise to the OFF position.
3. The A/C switch is manually turned OFF.
In other words, the compressor ON request cannot be turned off in D/F or DEF modes.