Toyota Tacoma (2015-2018) Service Manual: Terminals Of Ecu

Toyota Tacoma (2015-2018) Service Manual / Steering Column / Steering Lock System / Terminals Of Ecu

TERMINALS OF ECU

1. TERMINAL INSPECTION

Text in Illustration

Component without harness connected

(Steering Lock ECU (Steering Lock Actuator or UPR Bracket Assembly))

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

Terminal No. (Symbol)	Input/Output	Wiring Color	Terminal Description	Condition	Specified Condition	Related Data List Item
S45-1 (GND) - Body ground	-	W-B - Body ground	Ground*	Always	Below 1 Ω	-
S45-3 (IGE) - S45-1 (GND)	Input	Y - W-B	Steering lock motor activation command signal (motor activation command signal sent from certification ECU (smart key ECU assembly))	Any door opened when conditions below met, and then steering lock motor activated: Shift lever in P Steering lock unlocked in advance by carrying key and turning engine switch on (IG) After above conditions met, engine switch turned off	Pulse generation (see waveform)	Smart Key Power Supply Short Unlock Request Receive Lock Request Receive
S45-4 (SLP1) - S45-1 (GND)	Output	BE - W-B	Steering lock bar position signal (output signal from steering unlock sensor)	Steering locked → unlocked	11 to 14 V → Below 1.5 V	Smart Key Sensor Value
S45-5 (LIN) - S45-1 (GND)	Input/Output	L - W-B	LIN communication line	-	-	Smart Key Steering Lock Start Cond
S45-6 (IG2) - S45-1 (GND)	Input	B - W-B	Power source mode signal (IG2 power supply input for entire steering lock actuator assembly)*	Engine switch off → engine switch on (IG)	Below 1 V → 11 to 14 V	-
S45-7 (B) - Body ground	Input	R - Body ground	Power source*	Always	11 to 14 V	-

*: When there is a problem with the power source input, the certification ECU (smart key ECU assembly) may store DTC B2786.

NOTICE:

There is 1 motor and 2 sensors built into the steering lock actuator assembly.

HINT:

When taking measurements when the lock motor is stopped, it is not necessary to perform any operations.
In order to take measurements when the lock motor is operating, perform either of the following operations:
- To unlock the steering, carry the key and turn the engine switch on (ACC) or on (IG).
- To lock the steering, turn the engine switch off with the shift lever in P, and then open a door.

(1) Waveform

Item	Content
Tester Connection	S45-3 (IGE) - S45-1 (GND)
Tool Setting	2 V/DIV., 200 ms./DIV.
Vehicle Condition	Steering lock motor not operating → Operating → Not operating

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*a	Steering Lock Motor not Operating
*b	Steering Lock Motor Operating

Dtc Check / Clear

DTC CHECK / CLEAR NOTICE: The steering lock ECU (steering lock actuator or UPR bracket assembly) does not store history DTCs. If any DTCs are output, confirm and record them as soon ...

Data List / Active Test

DATA LIST / ACTIVE TEST 1. READ DATA LIST HINT: Using the Techstream to read the Data List allows the values or states of switches, sensors, actuators and other items to be read without removing ...

Other materials:

Precaution
PRECAUTION 1. PRECAUTIONS WHEN CHECKING FOR DTCS (a) When the cable is disconnected from the negative (-) battery terminal, the DTCs stored in the steering lock ECU (steering lock actuator or UPR bracket assembly) are cleared. Be sure to record any output DTCs immediately. (b) Normally, with ...

Reassembly
REASSEMBLY CAUTION / NOTICE / HINT HINT: Use the same procedure for the RH side and LH side. The following procedure is for the LH side. When installing a new front wheel opening extension pad or No. 1 front wheel opening extension pad or No. 2 front wheel opening extension pa ...

Lost Communication with Power Source Control (B278C)
DESCRIPTION DTC No. DTC Detection Condition Trouble Area B278C An internal malfunction occurs in the certification ECU (smart key ECU assembly) Certification ECU (smart key ECU assembly) CAUTI ...