Unlock Position Sensor Signal Circuit

STEERING COLUMN: STEERING LOCK SYSTEM: Unlock Position Sensor Signal Circuit
- Unlock Position Sensor Signal Circuit

DESCRIPTION

The steering lock ECU sends an unlock position signal to the main body ECU. On receiving the signal, the main body ECU permits engine start. (This prevents the engine from being started with the steering locked.)

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

WIRING DIAGRAM





INSPECTION PROCEDURE

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.

PROCEDURE

1. CHECK STEERING LOCK ECU





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

Standard Voltage:





NG -- CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU - BODY GROUND)
OK -- Continue to next step.

2. CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU - MAIN BODY ECU)

(a) Disconnect the E77 and E15 ECU connectors.





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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE STEERING LOCK ACTUATOR ASSEMBLY (STEERING LOCK ECU) Removal

3. CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU - BODY GROUND)





(a) Disconnect the E77 ECU connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

4. CHECK HARNESS AND CONNECTOR (BATTERY - STEERING LOCK ECU)





(a) Disconnect the E77 ECU connector.

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

Standard Voltage:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

5. CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU - MAIN BODY ECU)

(a) Disconnect the E77 and E15 ECU connectors.





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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE STEERING LOCK ACTUATOR ASSEMBLY (STEERING LOCK ECU) Removal