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Home >> Honda >> 2021 >> Pilot EX, AWD >> Repair and Diagnosis (Single Page) >> Heating, Ventilation & A/C (HVAC) >> HVAC Control Systems >> HVAC System - Service, Testing And Troubleshooting >> Connector View >> Hvac Control Unit Connector For Inputs and Outputs
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Hvac Control Unit Connector For Inputs and Outputs

Connector Index
HVAC Control Unit Connector A (32P) 
HVAC Control Unit Connector C (12P) 

HVAC Control Unit Connector A (32P) 

GHH309953Courtesy of HONDA, U.S.A., INC.
Cavity  Terminal name  Description  Signal 
1 IG2 A/C IG2 power source With vehicle in ON mode: battery voltage
2 ILLUMI+ Power source for illumination With combination light switch ON: battery voltage
3 Not used ------ ------
4 Not used ------ ------
5 SENSOR 5V Outputs sensor 5 V With vehicle in ON mode: about 5.0 V
6 Not used ------ ------
7 Not used ------ ------
8 Not used ------ ------
9 M COOL AS Outputs to drive front air mix control motor to COOL side With vehicle in ON mode and front air mix control motor moving to COOL: battery voltage
10 M HOT AS Outputs to drive front air mix control motor to HOT side With vehicle in ON mode and front air mix control motor moving to HOT: battery voltage
11 MDEF FR Outputs to mode control motor A to HEAT side With vehicle in ON mode and mode control motor A moving to HEAT: battery voltage
12 MVENT FR Outputs to mode control motor A to VENT side With vehicle in ON mode and mode control motor A moving to VENT: battery voltage
13 M-HEAT HD Outputs to mode control motor B to HEAT side With vehicle in ON mode and mode control motor B moving to HEAT: battery voltage
14 M-DEF HD Outputs to mode control motor B to DEF side With vehicle in ON mode and mode control motor B moving to DEF: battery voltage
15 M REC Outputs to drive recirculation control motor to RECIRCULATE side With vehicle in ON mode and recirculation control motor moving to RECIRCULATE: battery voltage
16 M FRS Outputs to drive recirculation control motor to FRESH side With vehicle in ON mode and recirculation control motor moving to FRESH: battery voltage
17 GND Ground for HVAC control unit (G405) With vehicle in ON mode: less than 0.2 V
18 SENSOR (COM) Sensor ground With vehicle in ON mode: less than 0.2 V
19 ILLUMI- (LED) Detects illumination control signal With combination light switch ON: changed voltage (depending on dashlights brightness controller)
20 PD SENSOR A/C Pressure sensor signal With A/C switch ON: about 0.7-4.6 V (depending on A/C pressure)
21 Not used ------ ------
22 Not used ------ ------
23 B-CAN_H B-CAN_H communication signal With vehicle in ON mode: pulses
Cavity  Terminal name  Description  Signal 
24 B-CAN_L B-CAN_L communication signal With vehicle in ON mode: pulses
25 M HOT RR Outputs to drive rear air mix control motor to HOT side With vehicle in ON mode and rear air mix control motor moving to HOT: battery voltage
26 M COOL RR Outputs to drive rear air mix control motor to COOL side With vehicle in ON mode and rear air mix control motor moving to COOL: battery voltage
27 M-HEAT RR Outputs to rear mode control motor to HEAT side With vehicle in ON mode and rear mode control motor moving to HEAT: battery voltage
28 M-VENT RR Outputs to rear mode control motor to VENT side With vehicle in ON mode and rear mode control motor moving to VENT: battery voltage
29 R-BLW-V Feedback signal of rear blower power transistor drain voltage With vehicle in ON mode: about 0 V - battery voltage (depending on rear blower motor speed)
30 R-BLW-G Outputs rear blower power transistor gate voltage With vehicle in ON mode, and rear fan control button OFF: less than 0.2 VWith vehicle in ON mode, and rear fan control button ON: about 4.0 V - battery voltage (depending on rear blower motor control)
31 BLOWER (V) Feedback signal of front blower power transistor drain voltage With vehicle in ON mode: about 0 V - battery voltage (depending on front blower motor speed)
32 BLOWER (G) Outputs front blower power transistor gate voltage With vehicle in ON mode, and front fan control button OFF: less than 0.2 VWith vehicle in ON mode, and front fan control button ON: about 4.0 V - battery voltage (depending on front blower motor control)

HVAC Control Unit Connector C (12P) 

GHH309954Courtesy of HONDA, U.S.A., INC.
Cavity  Terminal name  Description  Signal 
1 Not used ------ ------
2 AMDP AS Detects potentiometer signal of front air mix control motor (door position) With vehicle in ON mode: about 1.0-4.0 V (depending on front air mix control motor position)
3 MOD-P FR Detects potentiometer signal of mode control motor A (door position) With vehicle in ON mode: about 1.0-4.0 V (depending on mode control motor A position)
4 MOD-P HD Detects potentiometer signal of mode control motor B (door position) With vehicle in ON mode: about 1.74-4.0 V (depending on mode control motor B position)
5 FRS REC-P Detects potentiometer signal of recirculation control motor (door position) With vehicle in ON mode: about 1.0-4.0 V (depending on recirculation control motor position)
6 AMDP RR Detects potentiometer signal of rear air mix control motor (door position) With vehicle in ON mode: about 1.0-4.0 V (depending on rear air mix control motor position)
7 MOD-P RR Detects potentiometer signal of rear mode control motor (door position) With vehicle in ON mode: about 1.0-4.0 V (depending on rear mode control motor position)
8 Not used ------ ------
9 Not used ------ ------
10 Not used ------ ------
11 TEVA Inputs front evaporator temperature sensor signal ------
12 Not used ------ ------