Heating / Air Conditioning

Terminals Of Ecu

~6min read
TERMINALS OF ECU

1. A/C AMPLIFIER


HINT:

Check from the rear of the connector while it is connected to the A/C amplifier.

Terminal No.

(Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

D47-1 (IG+) - D47-14 (GND)

Y - W

Power source (IG)

Ignition switch ON

11 to 14 V

D47-1 (IG+) - D47-14 (GND)

Y - W

Power source (IG)

Ignition switch off

Below 1 V

D47-2 (SOL+) - D47-14 (GND)

L - W

A/C compressor solenoid operation signal

Engine running

A/C switch: on

Blower switch: LO

Pulse generation

(See waveform 1)

D47-5 (TAM) - D47-13 (GND)

V - L

Ambient temperature sensor signal

Ignition switch ON

Ambient temperature: 25 °C

1.35 to 1.75 V

D47-5 (TAM) - D47-13 (GND)

V - L

Ambient temperature sensor signal

Ignition switch ON

Ambient temperature: 40 °C

0.9 to 1.2 V

D47-8 (LOCK) - D47-13 (GND)*1

P - L

A/C compressor lock sensor signal

Engine running

Blower switch: LO

A/C switch: on

Pulse generation

(See waveform 2)

D47-9 (PRE) - D47-13 (GND)

R - L

A/C pressure sensor signal

Start engine, Operate A/C system, Refrigerant pressure: Abnormal pressure (more than 3140 kPa (32.0 kgf/cm2, 455 psi))

4.84 V or higher

D47-9 (PRE) - D47-13 (GND)

R - L

A/C pressure sensor signal

Start engine, Operate A/C system, Refrigerant pressure: Abnormal pressure (less than 196 kPa (2.0 kgf/cm2, 28 psi))

Below 0.73 V

D47-9 (PRE) - D47-13 (GND)

R - L

A/C pressure sensor signal

Start engine, Operate A/C system, Refrigerant pressure: Normal pressure (less than 3140 kPa (32.0 kgf/cm2, 455 psi) and more than 196 kPa (2.0 kgf/cm2, 28 psi))

0.73 to 4.84 V

D47-10 (S5-3) - D47-13 (GND)

P - L

Power supply for A/C pressure sensor

Ignition switch ON

A/C switch: on

4.75 to 5.25 V

D47-10 (S5-3) - D47-13 (GND)

P - L

Power supply for A/C pressure sensor

Ignition switch ON

A/C switch: off

Below 1 V

D47-11 (CANH) - D47-12 (CANL)

P - W

CAN communication system

CAN communication circuit

Pulse generation

D47-13 (GND) - Body ground

L - Body ground

Ground for A/C pressure sensor, A/C ambient temperature sensor, A/C lock sensor

Always

Below 1 V

D47-14 (GND) - Body ground

W - Body ground

Ground for main power supply

Always

Below 1 V

D47-18 (D) - D47-14 (GND)

G - W

DEF relay signal

Ignition switch ON

REAR DEF switch: on

Below 1 V

D47-18 (D) - D47-14 (GND)

G - W

DEF relay signal

Ignition switch ON

REAR DEF switch: off

11 to 14 V

D47-20 (MGC) - D47-14 (GND)*1

Y - W

A/C compressor magnetic clutch operation signal

Ignition switch ON

Blower switch: LO

A/C switch: off

11 to 14 V

D47-20 (MGC) - D47-14 (GND)*1

Y - W

A/C compressor magnetic clutch operation signal

Ignition switch ON

Blower switch: LO

A/C switch: on

Below 1 V

D47-21 (B) - D47-14 (GND)

V - W

Power source (Back-up)

Always

11 to 14 V

D47-23 (BLW) - D47-14 (GND)

R - W

Blower motor speed control signal

Ignition switch ON

Blower switch: LO

Pulse generation

(See waveform 3)

D47-29 (TR) - D47-34 (SG-1)

LG - V

Room temperature sensor signal

Ignition switch ON

Cabin temperature: 25 °C

1.8 to 2.2 V

D47-29 (TR) - D47-34 (SG-1)

LG - V

Room temperature sensor signal

Ignition switch ON

Cabin temperature: 40 °C

1.2 to 1.6 V

D47-32 (TSP) - D47-14 (GND)

LG - W

Solar sensor signal (for Front passenger side)

Ignition switch ON

Solar sensor subjected to electric light

0.8 to 4.3 V

D47-32 (TSP) - D47-14 (GND)

LG - W

Solar sensor signal (for Front passenger side)

Ignition switch ON

Solar sensor covered with a cloth

Below 0.8 V

D47-33 (TSD) - D47-14 (GND)

P - W

Solar sensor signal (for Driver side)

Ignition switch ON

Solar sensor subjected to electric light

0.8 to 4.3 V

D47-33 (TSD) - D47-14 (GND)

P - W

Solar sensor signal (for Driver side)

Ignition switch ON

Solar sensor covered with a cloth

Below 0.8 V

D47-34 (SG-1) - Body ground

V - Body ground

Ground for room temperature sensor

Always

Below 1 V

D47-37 (LIN1) - D47-14 (GND)

SB - W

LIN communication signal

Ignition switch ON

Pulse generation

z7-2 (BUS G) - Body ground

-

Ground for BUS IC

Always

Below 1 V

z7-3 (BUS) - z7-2 (BUS G)

-

BUS IC control signal

Ignition switch ON

Pulse generation

z7-4 (B BUS) - z7-2 (BUS G)

-

Power supply for BUS IC

Ignition switch off

Below 1 V

z7-4 (B BUS) - z7-2 (BUS G)

-

Power supply for BUS IC

Ignition switch ON

11 to 14 V

z7-5 (SGA) - Body ground

-

Ground for evaporator temperature sensor

Always

Below 1 V

z7-6 (TEA) - z7-5 (SGA)

-

A/C evaporator temperature sensor signal

Ignition switch ON

Evaporator temperature: 0 °C

1.7 to 2.1 V

z7-6 (TEA) - z7-5 (SGA)

-

A/C evaporator temperature sensor signal

Ignition switch ON

Evaporator temperature: 15 °C

0.9 to 1.3 V

  • *1: for 2GR-FE

(a) Waveform 1:


Item

Content

Terminal No.

D47-2 (SOL+) - D47-14 (GND)

Tool Setting

5 V/DIV., 500 μs/DIV.

Vehicle Condition

Engine running

A/C switch: on

(b) Waveform 2:


Item

Content

Terminal No.

D47-8 (LOCK) - D47-13 (GND)

Tool Setting

200 mV/DIV., 10 ms./DIV.

Vehicle Condition

Engine running

Blower switch: LO

A/C switch: on

(c) Waveform 3:


Item

Content

Terminal No.

D47-23 (BLW) - D47-14 (GND)

Tool Setting

1 V/DIV., 500 μs/DIV.

Vehicle Condition

Ignition switch ON

Blower switch: LO

2. AIR CONDITIONING CONTROL ASSEMBLY


HINT:

Check from the rear of the connector while it is connected to the air conditioning control assembly.

Terminal No.

(Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

E3-1 (ILL-) - E3-3 (ILL+)

L - BR

Light control switch signal

Light control switch: OFF

Below 1 V

E3-1 (ILL-) - E3-3 (ILL+)

L - BR

Light control switch signal

Light control switch: TAIL

11 to 14 V

E3-2 (LIN1) - E3-5 (GND)

SB - W

LIN communication signal

Ignition switch ON

Pulse generation

E3-4 (IG+) - E3-5 (GND)

GR - W

Power source (IG)

Ignition switch off

Below 1 V

E3-4 (IG+) - E3-5 (GND)

GR - W

Power source (IG)

Ignition switch ON

11 to 14 V

E3-5 (GND) - Body ground

W - Body ground

Ground for front air conditioning control assembly

Always

Below 1 V

Test yourself

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