HVAC Control Unit Inputs and Outputs

Fig 1: Identifying HVAC Control Unit 30P Connector Terminals

Courtesy of AMERICAN HONDA MOTOR CO., INC.

WIRE COLOR REFERENCE

Terminal nunver	Wire color	Terminal name	Discription	Signal
1	BLK	GND	Ground circuit (G401)	Lass then 0.5 V at all times
2	RED/BLK	SMALL	Illumination (+)	With combination light switch ON: battery voltage
3	RED	ILL-	Illumination control	With illumination switch ON: changed voltage (depending on dash light brightness controller)
8	PNK	TAM	Detects outside air temperature sensor signal	With ignition switch ON (II): about 1.0-4.0 V (depending on outside air temperature)
11	LT BLU	B-CAN	Sends communication signal	With ignition switch ON (II): pulses
12	YEL	ACS	Drives A/C signal	With ignition switch ON (II), A/C pressure switch ON, and A/C compressor clutch ON: less than 0.5 V With ignition switch ON (II), A/C pressure switch ON, and A/C compressor clutch OFF: battery voltage
13	GRN/RED	REC	Drives recirculation control motor	With ignition switch ON (II) and recirculation control motor change to the FRESH position: connected to ground at several seconds
14	GRN/WHT	FRS	Drives recirculation control motor	With ignition switch ON (II) and recirculation control motor change to the RECERCU position: connected to ground at several seconds
15	BLK/YEL	IG2	Power source for control unit (IG2)	With ignition switch ON (II): battery voltage
16	YEL/BLU	M-DEF	Drives mode control motor	With ignition switch ON (II) and mode control motor change to the VENT position: Less than 0.5 V at several seconds
17	YEL/RED	M-VENT	Drives mode control motor	With ignition switch ON (II) and mode control motor change to the DEF position: Less than 0.5 V at several seconds
18	GRN	M-COOL	Drives air mix control motor	With ignition switch ON (II) and air mix control motor change to the max HOT position: Less than 0.5 V at several seconds
19	PNK/BLU	M-HOT	Drives air mix control motor	With ignition switch ON (II) and air mix control motor change to the max COOL position: Less than 0.5 V at several seconds
20	RED/BLK	SENS-COM	Sensor ground	Less than 0.5 V at all times
22	GRY	S5V	Provides motor reference voltage	With ignition switch ON (II): about 5.0 V
23	PNK/BLK	AMD-P	Detects air mix potential signal	With ignition switch ON (II): about 0.5-4.5 V (depending on AIR MIX MOTOR position)
24	BRN	TEVA	Detects evaporator temperature sensor signal	With ignition switch ON (II): about 1.0-4.0 V (depending on evaporator temperature)
25	BLU/RED	BLW-V	Detects blower motor feedback	With ignition switch ON (II): about 0 V-battery voltage (depending on blower motor speed)
26	BLU/TEL	BLW-G	Drives power transistor	With ignition switch ON (II) and fan control switch OFF: less than 0.5 V With ignition switch ON (II) and fan control switch ON: about 4.0 V-battery voltage (depending on blower motor control)
27	YEL/GRN	MODE4	Detects mode control motor position signal	With ignition switch ON (II): less than 0.5 V or about 5.0 V (depending on MODE CONTROL MOTOR position)
28	WHT/BLU	MODE3	Detects mode control motor position signal	With ignition switch ON (II): less than 0.5 V or about 5.0 V (depending on MODE CONTROL MOTOR position)
29	RED/BLU	MODE2	Detects mode control motor position signal	With ignition switch ON (II): less than 0.5 V or about 5.0 V (depending on MODE CONTROL MOTOR position)
30	RED/YEL	MODE1	Detects mode control motor position signal	With ignition switch ON (II): less than 0.5 V or about 5.0 V (depending on MODE CONTROL MOTOR position)