Heating and Air Conditioning: Description and Operation

1. HEATER BLOWER MOTOR OPERATION
Current is applied at all times through the HTR fuse to TERMINAL 1 of the HEATER relay.
When the ignition SW is turned on, current flows through the GAUGE fuse to TERMINAL 5 of the HEATER relay to the coil side to TERMINAL 3 to TERMINAL 3 of the blower SW.
* Low speed operation
When the blower SW is moved to LO position, current flows to TERMINAL 3 of the blower SW to TERMINAL 1 to GROUND, causing the HEATER relay to switch on. This causes the current to flow from the HTR fuse to TERMINAL 1 of the HEATER relay to TERMINAL 2 to TERMINAL 1 of the blower motor to TERMINAL 2 to TERMINAL 4 of the blower resistor to TERMINAL 1 to GROUND, causing the blower motor to rotate at low speed.
* Medium speed operation (Operation at M1, M2)
When the blower SW is moved to M1 position, current flows to TERMINAL 3 of the blower SW to TERMINAL 1 to GROUND, turning the HEATER relay to switch on. This causes the current to flow from the HTR fuse to TERMINAL 1 of the HEATER relay to TERMINAL 2 to TERMINAL 1 of the blower motor to TERMINAL 2 to TERMINAL 4 of the blower resistor to TERMINAL 3 to TERMINAL 4 of the blower SW to TERMINAL 1 to GROUND. At this time, the blower resistance of the blower resistor is less than at low speed, so the blower motor rotates at medium low speed.
When the blower SW is moved to M2 position, current flows through the motor flows from TERMINAL 4 of the blower resistor to TERMINAL 2 to TERMINAL 8 of the blower SW to TERMINAL 1 to GROUND. At this time, resistance of the blower resistor is less than at M1 position, so the blower motor rotates at medium high speed.
* High speed operation
When the blower SW is moved to HIGH position, current flows to TERMINAL 3 of the blower SW to TERMINAL 1 to GROUND, turning the HEATER relay to switch on.
This causes the current to flow from the HTR fuse to TERMINAL 1 of the HEATER relay to TERMINAL 2 to TERMINAL 1 of the blower motor to TERMINAL 2 to TERMINAL 5 of the blower SW to TERMINAL 1 to GROUND, causing the blower motor to rotate at high speed.

2. OPERATION OF AIR INLET CONTROL SERVO MOTOR
* Switching from FRESH to RECIRC
With the ignition SW turned on, current flows from the GAUGE fuse to TERMINAL 7 of the air inlet control servo motor. When the RECIRC/FRESH SW is switched to the RECIRC side, current flows from TERMINAL 7 of the air inlet control servo motor to TERMINAL 1 to TERMINAL (A) 13 of the integration control and panel to TERMINAL (B) 1 to GROUND. The motor rotates and the damper moves to the RECIRC side. When it is in the RECIRC position, current is cut inside the servo motor and the damper stops at that position.
* Switching from RECIRC to FRESH
With the ignition SW turned on, when the RECIRC/FRESH SW is switched to the FRESH side, current flows from TERMINAL 7 of the air inlet control servo motor to TERMINAL 3 to TERMINAL (A) 15 of the integration control and panel to TERMINAL (B) 1 to GROUND, the motor rotates and the damper moves to the FRESH side. When it is in the FRESH position, current is cut inside the servo motor and the damper stops at that position. When the ignition SW turned on, and mode SW (Integration control and panel) is at DEF or F/DEF position, it causes the damper to move to the FRESH side. Whether the RECIRC/FRESH SW (Integration control and panel) is on or not.

3. AIR CONDITIONING OPERATION
When the blower SW is on, current flows from the GAUGE fuse to the HEATER relay (Coil side) to TERMINAL 3 of the blower SW to TERMINAL 1 to GROUND, activating the HEATER relay. This causes current to flow from the HTR fuse to the HEATER relay (Point side) to A/C fuse to TERMINAL (B) 12 of the A/C SW (Integration control and panel). When the A/C SW (Integration Control and panel) is turned on. Current flows from the GAUGE fuse to TERMINAL (B) 4 of the integration control and panel to TERMINAL (A) 8 to A/C magnetic clutch. Causing The compressor to operate.
When blower SW is on and mode SW (Integration control and panel) is at DEF or F/DEF position, it causes A/C to run whether A/C SW (Integration control and panel) is on or not.