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Fig. 41: Checking Wire Harness (Steering Lock ECU -Transponder Key Amplifier)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS AND CONNECTOR
OK: Go to next step
5.CHECK OPERATION OF TRANSPONDER KEY AMPLIFIER
a. After replacing the transponder key amplifier with a normally functioning amplifier, check that the
engine starts.
OK: Engine starts.
NG: REPLACE STEERING LOCK ECU
OK: END
CIRCUIT DESCRIPTION
This DTC is output when: 1) the ECM detects errors in its own communications with the steering lock ECU; 2)
the ECM detects errors in the communication lines; and 3) the ECU communication ID between the steering
lock ECU and the ECM are different and an engine start is attempted.
Before troubleshooting for this DTC, make sure no steering lock ECU DTCs are present. If the steering lock
ECU has a key code related DTC, repair it first.
Fig. 42: Engine Immobilizer System Malfunction Circuit Description
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
WIRING DIAGRAM
Page 3219 of 4500
Fig. 43: Engine Immobilizer System Malfunction - Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.CHECK WIRE HARNESS (STEERING LOCK ECU - ECM)
a. Disconnect the S46 ECU connector.
b. Disconnect the E2 ECM connector
c. Measure the resistance of the wire harness side connectors.
Standard:
STEERING LOCK ECU - ECM - RESISTANCE TABLE
Tester connectionSpecified condition
S46-13 (EFIO) - E2-6 (IMI)Below 1 ohms
S46-4 (EFII) - E2-7 (IMO)Below 1 ohms
S46-13 (EFIO) or E2-6 (IMI) - Body ground10 kohms or higher
S46-4 (EFII) or E2-7 (IMO) - Body ground10 kohms or higher
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Fig. 44: Checking Wire Harness (Steering Lock ECU -ECM)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS AND CONNECTOR
OK: REPLACE ECM
CIRCUIT DESCRIPTION
This circuit provides power to operate the steering lock ECU.
WIRING DIAGRAM
Fig. 45: ECU Power Source Circuit
- Wiring Diagram
Page 3222 of 4500
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.INSPECT FUSE (MPX-B1, AM2, STR LOCK, D/C CUT)
a. Remove the MPX-B1, AM2 and STR LOCK fuses from the passenger side J/B.
b. Remove the D/C CUT fuse from the FL block.
c. Measure the resistance of the fuse.
Standard: Below 1 ohms
NG: REPLACE FUSE
OK: Go to next step
2.CHECK WIRE HARNESS (STEERING LOCK ECU - BATTERY AND BODY GROUND)
a. Disconnect the S46 ECU connector.
b. Measure the resistance and voltage of the wire harness side connector.
Standard:
STEERING LOCK ECU - BATTERY AND BODY GROUND - RESISTANCE TABLE
Tester connectionConditionSpecified condition
S46-1 (CPUB) - Body groundAlways10 to 14 V
S46-2 (IG2) - Body groundIgnition switch OFF -> ON0 V -> 10 to 14 V
S46-10 (+B) - Body groundAlways10 to 14 V
S46-9 (GND) - Body groundAlwaysBelow 1 ohms
Page 3223 of 4500
Fig. 46: Checking Wire Harness (Steering Lock ECU - Battery & Body Ground)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS AND CONNECTOR
OK: REPLACE STEERING LOCK ECU
Page 3224 of 4500
SYSTEM REFERENCE TABLE
System NameProceed To
Front Power Seat Control SystemINITIALIZATION