Toyota 4Runner: Power Source Control ECU Malfunction (B2782)

Toyota 4Runner Service Manual / Steering / Steering Column / Steering Lock System / Power Source Control ECU Malfunction (B2782)

DESCRIPTION

The steering lock ECU activates the steering lock motor with the power from the power management control ECU through the IGE circuit. This prevents the steering from being locked while the vehicle is moving.

If NG (PAST) is displayed for Power Supply Open in the Data List, perform troubleshooting according to the procedures below.

The diagnosis information of the steering lock ECU is transmitted to the Techstream via the certification ECU as the steering lock actuator assembly (steering lock ECU) is not connected to the CAN communication system.

DTC Code	Detection Condition	Trouble Area
B2782	An IGE power supply circuit malfunction.	Steering lock actuator assembly (steering lock ECU) Power management control ECU Harness or connector

WIRING DIAGRAM

CAUTION / NOTICE / HINT

HINT:

When the engine switch is off, the main body ECU may occasionally go into a non-active state called sleep mode. Therefore, before proceeding with the inspection, it is necessary to perform the following steps to wake up the ECU:

With the engine switch off, open the driver door. Then (with the engine switch still off) open and close any door several times at 1.5 second intervals.

NOTICE:

When disconnecting the cable from the negative (-) battery terminal, some systems need to be initialized after the cable is reconnected (See page ).

If the steering lock actuator assembly (steering lock ECU) is replaced, with the engine switch off and the shift lever in P, open and close the driver side door to record the current lock position into the steering lock ECU. If this is not performed, the engine may not start.
When replacing the steering lock ECU, registration must be performed (See page ).

PROCEDURE

1.	INSPECT STEERING LOCK ECU

(a) Disconnect the F68 steering lock ECU connector.

(b) Turn the engine switch off, make sure that the steering lock is unlocked and move the shift lever to P.

Standard Resistance:

Tester Connection	Condition	Specified Condition
F68-1 (GND) - Body ground	Always	Below 1 Ω

Text in Illustration

*a	Front view of wire harness connector (to Steering Lock ECU)

(d) Reconnect the F68 steering lock ECU connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
F68-3 (IGE) - F68-1 (GND)	Driver side door opened	Below 1 V (Steering lock motor operating)
F68-3 (IGE) - F68-1 (GND)	Driver side door opened	11 to 14 V (Steering lock motor not operating)

HINT:

When the steering lock is locked and the engine is switch is turned on (IG), the steering lock motor activates to release the steering lock. The motor operates for 2 to 15 seconds.

Text in Illustration

*a	Component with harness connected (Steering Lock ECU)

GO TO STEP 4

CLEAR DTC

(a) Clear the DTCs (See page ).

(b) Disconnect and reconnect the cable to the negative (-) battery terminal to clear the malfunction history of Power Supply Open.

3.	READ VALUE USING TECHSTREAM (POWER SUPPLY OPEN)

(a) Check for DTCs (See page ).

(b) Use the Data List to check if the steering lock control is functioning properly.

Smart Key

Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
Power Supply Open	Open in ECU record/NG (PAST) or OK	NG (PAST): Open in ECU OK: No malfunction	-

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

Power Supply Open

Open in ECU record/NG (PAST) or OK

NG (PAST): Open in ECU

OK: No malfunction

Result

Result	Proceed to
B2782 is not output "OK" is displayed on the Techstream.	A
B2782 is output "NG (PAST)" is displayed on the Techstream.	B

USE SIMULATION METHOD TO CHECK

REPLACE STEERING LOCK ACTUATOR ASSEMBLY (STEERING LOCK ECU)

4.	CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU - POWER MANAGEMENT CONTROL ECU)

(a) Disconnect the F80 power management control ECU connector.

(b) Disconnect the F68 steering lock ECU connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
F68-3 (IGE) - F80-8 (SLR+)	Always	Below 1 Ω
F68-3 (IGE) or F80-8 (SLR+) - Body ground	Always	10 kΩ or higher

REPLACE POWER MANAGEMENT CONTROL ECU

REPAIR OR REPLACE HARNESS OR CONNECTOR

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