Terminals Of Ecu

CHECK POWER STEERING ECU

Fig 1: Identifying Terminals Of ECU Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT:

As connector "a2" uses a lock lever, each terminal cannot be checked while the connector is still connected to the power steering ECU.

CONNECTOR TERMINAL REFERENCE

Terminal No. (Symbol)	Wiring Color	Terminal Description
a2-1 (MW)	R	W phase motor output
a3-2 (MU)	B	U phase motor output
a2-3 (MV)	W	V phase motor output

Measure the voltage and resistance according to the value(s) in the table below.

NOTE: When the P/S warning light is illuminated during a malfunction, the fail-safe function may cause the voltage of the power steering ECU terminals to become 0 V.

CONNECTOR TERMINAL REFERENCE

Terminal No. (Symbol)	Wiring Color	Terminal Description	Condition	Specified Condition
A23-1 (PIG) - A23-2 (PGND)	L - W-B	Power source	Always	11 to 14 V
A23-2 (PGND) - Body ground	W-B - Body ground	Power ground	Always	Below 1 Ω
E51-1 (CANH) - E51-7 (CANL)	SB-W	CAN communication line	Ignition switch off	54 to 69 Ω
E51-6 (IG) - A23-2 (PGND)	L - W-B	IG power source	Ignition switch ON	11 to 14 V
a1-1 (RSIN) - A23-2 (PGND)	-W-B	Rotation angle sensor SIN aspect output signal	Ignition switch ON Steering wheel is turned	0.68 to 4.42 V
a1-2 (RCOS) - A23-2 (PGND)	-W-B	Rotation angle sensor COS aspect output signal	Ignition switch ON Steering wheel is turned	0.68 to 4.42 V
a1-4 (RGND) - A23-2 (PGND)	-W-B	Rotation angle sensor excitation circuit GND	Always	Below 1 Ω
a1-6 (R+) - A23-2 (PGND)	-W-B	Rotation angle sensor excitation output signal	Ignition switch ON Steering wheel is turned	0.68 to 4.42 V
Connector A-5 (TRQ1) -Connector A-8 (TRQG)	-	Torque sensor signal	Ignition switch ON Steering wheel is not turned (without load)	2.3 to 2.7 V
			Ignition switch ON Steering wheel is turned to right with vehicle stopped	2.5 to 3.8 V
			Ignition switch ON Steering wheel is turned to left with vehicle stopped	1.2 to 2.5 V
Connector A-6 (TRQV) - Connector A-8 (TRQG)	-	Torque sensor voltage source	Ignition switch ON	4.5 to 5.5 V
Connector A-7 (TRQ2) -Connector A-8 (TRQG)	-	Torque sensor signal	Ignition switch ON Steering wheel is not turned (without load)	2.3 to 2.7 V
			Ignition switch ON Steering wheel is turned to right with vehicle stopped	1.2 to 2.5 V
			Ignition switch ON Steering wheel is turned to left with vehicle stopped	2.5 to 3.8 V
Connector A-8 (TRQG) -Body ground	- Body ground	Torque sensor ground	Always	Below 1 Ω

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