Terminals Of Ecu

CHECK 4WD CONTROL ECU

Fig 1: Identifying Terminals Of ECU

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the voltage and resistance of the connector.

Symbols (Terminal No.)	Wiring Color	Terminal Description	Condition	Specified Condition
CANH (E57-14) - CANL (E57-16)	P - W	CAN communication	Ignition switch off	54 to 69 Ω
GND (E57-23) - Body ground	W-B - Body ground	Ground	Always	Below 1 Ω
4WDL (E57-7) - Body ground	R - Body ground	Ground	4WD lock mode switch ON	Below 1 Ω
IG1 (E57-11) - GND (E57-23)	L - W-B	Power source voltage	Ignition switch ON	10 to 14 V
SLC+ (E57-13) - SLC- (E57-32)	W - B	4WD linear solenoid signal	Ignition switch ON	Pulse generation (See Fig 2waveform 1)
BSLC (E57-9) - GND (E57-23)	R - W-B	Power source voltage	Ignition switch ON	10 to 14 V

If the result is not as specified, the 4WD control ECU may have a malfunction.

Using an oscilloscope, check the waveform 1.

Fig 2: Waveform 1 Graph

WAVEFORM 1 (REFERENCE)

Symbols (Terminal No.)	Content
Tool setting	5 V/DIV., 2 msec. / DIV.
Vehicle condition	Engine stop, ignition switch ON