Terminals Of Ecu

WARNING: This page is about a different car, the 2008 Toyota Yaris. However, it is still accessible from the selected car via links, so may be relevant.

CHECK AIR CONDITIONING AMPLIFIER

Fig 1: Identifying ECU Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT:

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

TERMINAL DESCRIPTION AND SPECIFIED CONDITION

Symbols (Terminals No.)

Wiring Color

Terminal Description

Condition

Specified Condition

S5-3(E8-1)-GND(E8-12)

Y-W-B

Power supply for pressure sensor

Ignition switch: ON

4.5 to 5.5 V

TX+(E8-2)-GND(E8-12)

V-W-B

CAN communication line

Ignition switch: ON

Pulse generation (see WAVEFORM 1 )

TX-(E8-3)-GND(E8-12)

W-W-B

CAN communication line

Ignition switch: ON

Pulse generation (see WAVEFORM 2 )

SG-2 (E8-4) - Body ground

L - Body ground

Ground for evaporator temperature sensor

Always

Below 1.0 Ω

TAM (E8-5) - SG-1 (E8-11)

W-B

Ambient temperature sensor signal

Ignition switch: ON

1.35 to 1.75 V

Ambient temperature: 25 °C

PRE (E8-6) - SG-1 (E8-11)

GR-B

A/C pressure sensor signal

Refrigerant pressure: normal

0.76 to 4.74 V

PRE (E8-6) - SG-1 (E8-11)

GR-B

A/C pressure sensor signal

Refrigerant pressure: abnormal (less than 0.196 MPa [2.0 kgf/cm² ] or more than 3.14 MPa [32 kgf/cm² ])

Below 0.76 V or 4.74 V or more

SOL+ (E8-7) - GND (E8-12)

LG - W-B

A/C compressor operation signal

Engine idling

Pulse generation (see WAVEFORM 3 )

Blower switch: 1

A/C switch: ON

IG+(E8-8)-GND(E8-12)

Y - W-B

Power source (IG)

Ignition switch: ON

11 to 14 V

SBLW (E8-9) - GND (E8-12)

BR - W-B

Blower motor ON signal

Ignition switch: ON

11 to 14 V --> 0V

Blower switch: 0 --> 1

TE(E8-10)-SG-2(E8-4)

GR-L

Evaporator temperature sensor signal

Ignition switch: ON

1.0 to 1.3 V

Temperature near evaporator: 15°C (59°F)

SG-1 (E8-11)-Body ground

B - Body ground

Ground for ambient temperature sensor

Always

Below 1.0 Ω

GND (E8-12)-Body ground

W-B - Body ground

Ground for main power supply

Always

Below 1.0Ω

A/C(E8-15)-GND(E8-12)

LG - W-B

A/C switch signal

Ignition switch: ON

Below 1 V --> 11 to 14 V

Defroster: OFF

A/C switch: OFF --> ON

Defroster mode detection switch signal

Ignition switch: ON

Below 1 V --> 11 to 14 V

A/C switch: OFF

Defroster: OFF --> ON

LED (E8-16)-Body ground

P - Body ground

A/C switch indicator signal

Engine idling

11 to 14 V --> Below 4 V

A/C switch: ON

Blower switch: 0 --> 1

PTC1⁽¹⁾(E9-9)-GND(E8-12)

V-W-B

PTC heater relay operation signal

Engine idling

Below 1 --> 11 to 14 V

No. 3 heater control knob: Max Hot

Engine coolant temperature: Below 65°C (149°F)

Ambient temperature: Below 10°C (50°F)

Blower switch: 0 --> 1

Waiting time: 10 seconds

PTC2⁽¹⁾(E9-10)-GND(E8-12)

BR - W-B

PTC heater relay operation signal

Engine idling

Below 1 V --> 11 to 14 V

No. 3 heater control knob: Max Hot

Engine coolant temperature: Below 65°C (149°F)

Ambient temperature: Below 10°C (50°F)

Blower switch: 0 --> 1

Waiting time: 20 seconds

PTC3⁽¹⁾(E9-12)-GND(E8-12)

R-W-B

PTC heater relay operation signal

Engine idling

Below 1 V --> 11 to 14 V

No. 3 heater control knob: Max Hot

Engine coolant temperature: Below 65°C (149°F)

Ambient temperature: Below 10°C(50°F)

Blower switch: 0 --> 1

Waiting time: 30 seconds

HEAT⁽¹⁾ (E9-14) - Body ground

LG - Body ground

MAX HOT switch detection signal

Ignition switch: ON

11 to 14 V

No. 3 heater control knob: Max Hot

HLS⁽¹⁾ (E9-23) - Body ground

LG - Body ground

Headlight control signal

Engine idling

11 to 14 V --> Below 1 V

Light control switch: OFF --> HEAD

ALT⁽¹⁾ (E9-24) - GND (E8-12)

P-W-B

Alternator operation signal

Engine idling

Pulse generation

⁽¹⁾	w/ PTC heater

Waveform 1 (Reference): Using an oscilloscope

CAN communication signal

WAVEFORM REFERENCE

Terminal Name	Between TX+ (E8-2) - GND (E8-12)
Tester Range	1 V/DIV, 10 μsec./DIV.
Condition	Ignition switch ON

HINT:

The waveform varies depending on the CAN communication signal.

Fig 2: Waveform Graph (Waveform 12)

Waveform 2 (Reference): Using an oscilloscope

CAN communication signal

WAVEFORM REFERENCE

Terminal Name	Between TX- (E8-3) - GND (E8-12)
Tester Range	1 V/DIV, 10 μsec./DIV.
Condition	Ignition switch ON

HINT:

The waveform varies depending on the CAN communication signal.

Fig 3: Waveform Graph (Waveform 13)

Waveform 3 (Reference): Using an oscilloscope

Compressor and pulley operation signal

WAVEFORM REFERENCE

Terminal Name	Between SOL+ (E8-7) - GND (E8-12)
Tester Range	5 V/DIV, 500 μsec. / DIV.
Condition	Engine idling, Blower switch 1, A/C switch ON

Fig 4: Waveform Graph - Compressor And Pulley Operation Signal