Terminals Of Ecu

CHECK 4WD ECU

Fig 1: 4WD ECU Control Connector Terminal Identification

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Measure the voltage and resistance of the connector.

Terminal No. (Symbol)	Terminal Description	Condition	Specified Condition
7 (4WDL) - Body ground	4 wheel drive control switch signal	Engine switch on (IG) and Press continuously 4 wheel drive control switch ON	Below 1 V
14 (CANH) - 16 (CANL)	CAN communication	Engine switch off	54 to 69 Ω
23 (GND) - Body ground	Ground	Engine switch off	Below 1 Ω
11 (IG1) - 23 (GND)	Power source voltage	Engine switch on (IG)	10 to 14 V
13 (SLC+) - 32 (SLC-)	4WD linear solenoid signal	D position, Idling	Pulse generation (See waveform 1 below)
9 (BSLC) - 23 (GND)	Power source voltage	Always	10 to 14 V

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

Using an oscilloscope, check the waveform 1.

Fig 2: Identifying Waveform 1

WAVEFORM 1 (REFERENCE)

Terminal Name	Content
Tester Range	5 V/DIV., 1 msec./DIV.
Condition	D position, Idling