Home Steering Steering Column VARIABLE GEAR RATIO STEERING: VARIABLE GEAR RATIO STEERING SYSTEM
Last Modified: 11-27-2007 1.6 J
Service Category: Steering Section: Steering Column
Model Year: 2008 Model: LX570 Doc ID: RM000000YQL00JX
Title: VARIABLE GEAR RATIO STEERING: VARIABLE GEAR RATIO STEERING SYSTEM: INSPECTION PROCEDURE (2008 LX570)

VGRS System Stops or does not Operate

INSPECTION PROCEDURE

HINT:

This problem may be caused by a malfunction in the vehicle stability control system or steering system.

Make sure that no DTC is output for the skid control ECU or steering control ECU before proceeding with the following procedures.

If a DTC is output for either of these ECUs, first troubleshoot it and then proceed to the troubleshooting below.

PROCEDURE

1.

READ VALUE USING TECHSTREAM (RECORD OF OVERHEAT)

(a) Use the Data List to check if the record of overheat is functioning properly.

VGRS

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

Motor Overheat Record

Record of continuous overheat preventive control/Rec or Unrec

Rec or Unrec

-

Result

Result

Proceed to

"Rec" (Record of motor overheating)

A

"Unrec" (No record of motor overheating)

B

HINT:

If "Rec" is displayed, reset the setting to "Unrec". Enter the VGRS menu on the Techstream, select record clearance, and follow the prompts to set to "Unrec".

A

2.

CHECK HEAT PROTECTION FUNCTION FOR STEERING ACTUATOR

(a) Turn the engine switch on (IG) and wait for 30 minutes until the steering actuator cools down.

(b) Start the engine and slowly turn the steering wheel from lock to lock (approximately 90°/sec.) 3 times.

HINT:

If turning the steering wheel quickly while driving at low speeds, the steering angle may differ between the left and right, or the steering wheel may become off-center.

However, this is not a malfunction.

(c) Check the number of turns from lock to lock.

Result

Result

Proceed to

3.2 turns

A

2.7 turns

B

A

3.

CHECK STEERING EFFORT

(a) Start the engine.

(b) Turn the steering wheel.

(c) Measure the steering effort.

Standard steering effort:

Below 6.9 N*m (70 kgf*cm, 61 in.*lbf)

HINT:

After completing the inspection or repair, attempt to simulate the problem and then perform "Read Value Using Techstream" above again to reconfirm that the problem does not occur.

OK

4.

CHECK STEERING ACTUATOR

(a) Check for abnormal noise or vibration in the steering actuator.

OK:

Neither abnormal noise nor vibration occurs.

OK

5.

CHECK STEERING CONTROL ECU (POWER SOURCE CIRCUIT)



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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

E82-3 (IG) -

Body ground

Engine switch on (IG)

11 to 14 V

E82-8 (PIG) -

Body ground

(b) Turn the engine switch off.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

E82-7 (PGND) -

Body ground

Always

Below 1 Ω

OK