Home Steering Steering Column STEERING LOCK SYSTEM
Last Modified: 11-27-2007 1.6 C
Service Category: Steering Section: Steering Column
Model Year: 2008 Model: LX570 Doc ID: RM000001T1K00BX
Title: STEERING COLUMN: STEERING LOCK SYSTEM: DESCRIPTION (2008 LX570)

DTC

B2788

IG2 Signal Malfunction

DESCRIPTION

The steering lock ECU determines the on/off status of the engine switch through the IG2 signal circuit.

After receiving an integration relay (IG2 relay) on signal, the steering lock ECU determines that the vehicle is moving.

The steering lock ECU does not lock the steering when it receives the integration relay (IG2 relay) on signal. This prevents the steering from being locked while the vehicle is moving.

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

DTC Code

Detection Condition

Trouble Area

B2788

An open or short in the IG2 signal circuit.

  • Steering lock actuator assembly (steering lock ECU)
  • IGN fuse
  • IG2 MAIN fuse
  • Integration relay (IG2 relay)
  • Main body ECU
  • Harness or connector

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.

INSPECT STEERING LOCK ECU



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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

E26-6 (IG2) - E26-1 (GND)

Engine switch off

Below 1 V

E26-6 (IG2) - E26-1 (GND)

Engine switch on (IG)

11 to 14 V

OK

3.

INSPECT FUSE (IGN, IG2 MAIN)

(a) Remove the IGN and IG2 MAIN fuses from the engine room relay block.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

IGN fuse

Always

Below 1 Ω

IG2 MAIN fuse

Always

Below 1 Ω

OK

4.

INSPECT INTEGRATION RELAY (IG2 RELAY)



(a) Remove the integration relay from the engine room relay block.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

1B-8 - 1C-1

Battery voltage applied to terminals 1B-6 and 1B-7

Below 1 Ω

1B-8 - 1C-1

Battery voltage not applied to terminals 1B-6 and 1B-7

10 kΩ or higher

OK

5.

CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU - INTEGRATION RELAY (IG2 RELAY) AND BODY GROUND)



(a) Disconnect the E26 steering lock ECU connector.

(b) Disconnect the 1B and 1C integration relay connectors.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

1C-1 - Body ground

Always

11 to 14 V

Standard Resistance:

Tester Connection

Condition

Specified Condition

E26-6 (IG2) - 1B-8

Always

Below 1 Ω

E26-6 (IG2) or 1B-8 - Body ground

Always

10 kΩ or higher

OK

6.

CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - INTEGRATION RELAY (IG2 RELAY) AND BODY GROUND)



(a) Disconnect the E2 main body ECU connector.

(b) Disconnect the 1B integration relay connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

E2-11 (IG2D) - 1B-6

Always

Below 1 Ω

1B-7 - Body ground

Always

Below 1 Ω

E2-11 (IG2D) or 1B-6 - Body ground

Always

10 kΩ or higher

OK