SYSTEM OUTLINE\n\n1. HEATER BLOWER OPERATION\n\nMANNAL BLOWER OPERATION\n\nWHEN THE BLOWER CONTROL SW IS SET TO ANY BLOWER SPEEDS, THE A/C AMPLIFIER OPERATES AND THE CURRENT TO DRIVE THE BLOWER MOTOR FLOWS FROM TERMINAL BLW OF THE A/C AMPLIFIER TO TERMINAL SI OF THE BLOWER MOTOR CONTROL RELAY. THE CURRENT ACTIVATES THE RELAY AND THE VOLTAGE APPLIED TO TERMINAL +B OF THE BLOWER MOTOR CONTROL RELAY IS OUTPUT AT TERMINAL M+ AS THE VOLTAGE FOR THE SELECTED BLOWER SPEED. THE CURRENT THEN FLOWS FROM TERMINAL M+ OF THE BLOWER MOTOR CONTROL RELAY TO TERMINAL 2 → TERMINAL 1 → TERMINAL M→ TERMINAL M-OF BLOWER MOTOR CONTROL RELAY → TERMINAL GND → GROUND, AND THE BLOWER MOTOR OPERATES AT THE BLOWER SPEED SELECTED.\n\nAUTO FUNCTION\n\nWHEN THE AUTO SW IS TURNED ON, THE A/C AMPLIFIER CALCULATES THE REQUIRED VENT TEMPERATURE BASED ON THE SET TEMPERATURE AND INPUT FROM EACH SENSOR. THEN TERMINAL BLW OF THE A/C AMPLIFIER INPUTS CURRENT TO TERMINAL SI OF THE BLOWER MOTOR CONTROL RELAY IN CONFORMITY WITH THE REQUIRED VENT OUTPUT. THIS CURRENT ACTIVATES THE BLOWER MOTOR CONTROL RELAY SO THAT CURRENT FLOWS FROM TERMINAL M+ OF THE BLOWER MOTOR CONTROL RELAY → TERMINAL 2 OF BLOWER MOTOR → TERMINAL 1 → TERMINAL M- OF BLOWER MOTOR CONTROL RELAY → TERMINAL GND → GROUND, ACTIVATING THE BLOWER MOTOR. THE BLOWER MOTOR THEN OPERATES AT DIFFERENT STEPS IN CONFORMITY WITH VARIABLE CURRENT FLOW OUTPUT FROM TERMINAL BLW OF THE A/C AMPLIFIER TO TERMINAL SI OF THE BLOWER MOTOR CONTROL RELAY.\n\n2. OPERATION OF AIR INLET CONTROL SERVO MOTOR\n\n(SWITCHING FROM FRESH TO RECIRC)\n\nWITH IGNITION SW TURNED ON, THE CURRENT FLOWS FROM HTR FUSE TO TERMINAL 2 OF AIR INLET CONTROL SERVO MOTOR → TERMINAL 5 → TERMINAL AIF OF A/C AMPLIFIER → TERMINAL GND → GROUND. THE MOTOR ROTATES AND THE DAMPER STOPS AT RECIRC POSITION.\n\n(SWITCHING FROM RECIRC TO FRESH)\n\nWITH IGNITION SW TURNED ON, THE CURRENT FLOWS FROM HTR FUSE TO TERMINAL 2 OF AIR INLET CONTROL SERVO MOTOR → TERMINAL 3 → TERMINAL AIF OF A/C AMPLIFIER → TERMINAL GND → GROUND. THE MOTOR ROTATES AND THE DAMPER STOPS AT FRESH POSITION.\n\n3. OPERATION OF AIR VENT MODE CONTROL SERVO MOTOR\n\nWITH IGNITION SW TURNED ON, THE CURRENT FLOWS FROM HTR FUSE TO TERMINAL IG OF A/C AMPLIFIER\n\n(SWITCHING FROM DEF TO FACE)\n\nTHE CURRENT FROM TERMINAL AOF OF A/C AMPLIFIER → TERMINAL 1 OF AIR VENT MODE CONTROL SERVO MOTOR → TERMINAL 2 → TERMINAL AOD OF A/C AMPLIFIER → TERMINAL GND → GROUND. THE MOTOR ROTATES AND THE DAMPER MOVES TO FACE SIDE. WHEN THE DAMPER OPERATES WITH THE A/C SW AT FACE POSITION, THE DAMPER POSITION SIGNAL IS INPUT FROM TERMINAL 3 OF THE SERVO MOTOR TO THE TERMINAL TPO OF THE A/C AMPLIFIER. AS A RESULT, CURRENT TO THE SERVO MOTOR CIRCUIT IS CUT OFF BY THE AMPLIFIER, SO THE DAMPER STOPS AT THAT POSITION.\n\n(SWITCHING FROM FACE TO DEF)\n\nTHE CURRENT FLOWS FROM TERMINAL AOD OF A/C AMPLIFIER → TERMINAL 2 OF AIR VENT MODE CONTROL SERVO MOTOR → TERMINAL 1 → TERMINAL AOF OF A/C AMPLIFIER → TERMINAL GND → GROUND. THE MOTOR ROTATES AND THE DAMPER STOPS AT THAT POSITION.\n\n4. OPERATION OF AIR MIX CONTROL SERVO MOTOR\n\nWHEN THE TEMPERATURE SW IS TURNED TO THE \"COOL\" SIDE, THE CURRENT FLOWS FROM TERMINAL AMC OF A/C AMPLIFIER → TERMINAL 1 OF AIR MIX CONTROL SERVO MOTOR → MOTOR → TERMINAL 2 → TERMINAL AMH OF A/C AMPLIFIER → TERMINAL GND → GROUND AND THE MOTOR ROTATES. THE DAMPER OPENING ANGLE AT THIS TIME IS INPUT FROM TERMINAL 3 OF SERVO MOTOR TO TERMINAL TP OF A/C CONTROL ASSEMBLY, THIS IS USED TO DETERMINE THE DAMPER STOP POSITION AND MAINTAIN THE SET TEMPERATURE.\n\nWHEN THE TEMPERATURE CONTROL SW IS TURNED TO THE \"WARM\" SIDE, THE CURRENT FLOWS FROM TERMINAL AMH OF A/C AMPLIFIER → TERMINAL 2 OF AIR MIX CONTROL SERVO MOTOR → MOTOR → TERMINAL 1 → TERMINAL AM1 OF A/C AMPLIFIER, ROTATING THE MOTOR IN REVERSE AND SWITCHING THE DAMPER FROM COOL TO WARM SIDE.