Home Vehicle Interior Supplemental Restraint Systems OCCUPANT CLASSIFICATION SYSTEM
Last Modified: 11-27-2007 1.6 D
Service Category: Vehicle Interior Section: Supplemental Restraint Systems
Model Year: 2008 Model: LX570 Doc ID: RM0000010VJ031X
Title: SUPPLEMENTAL RESTRAINT SYSTEMS: OCCUPANT CLASSIFICATION SYSTEM: DIAGNOSIS SYSTEM (2008 LX570)

DIAGNOSIS SYSTEM

1. SYMPTOM SIMULATION

HINT:

The most difficult case in troubleshooting is when no problem symptoms occur. In such a case, a thorough problem analysis must be carried out. A simulation of the same or similar conditions and environment in which the problem occurred in the customer's vehicle should be carried out. No matter how much skill or experience a technician has, troubleshooting without confirming the problem symptoms will lead to important repairs being overlooked and mistakes or delays.


(a) Vibration method: When vibration seems to be the major cause.

HINT:

Perform the simulation method only during the primary check period (for approximately 6 seconds after the engine switch is turned on (IG)).

(1) Slightly vibrate the part of the sensor considered to be the problem cause with your fingers and check whether the malfunction occurs.

NOTICE:

Shaking the relays too strongly may result in open relays.

(2) Slightly shake the connector vertically and horizontally.

(3) Slightly shake the wire harness vertically and horizontally.

HINT:

The connector joint and fulcrum of the vibration are the major areas to be checked thoroughly.

2. FUNCTION OF PASSENGER AIRBAG ON/OFF INDICATOR

(a) Initial check:

(1) Turn the engine switch on (IG).

(2) The passenger airbag ON/OFF indicator ("ON" and "OFF") comes on for approximately 4 seconds, then goes off for approximately 2 seconds.

(3) Approximately 6 seconds after the engine switch is turned on (IG), the passenger airbag ON/OFF indicator will show ("ON" or "OFF") depending on the conditions listed below.

Condition

ON Indicator

OFF Indicator

Vacant

Off

Off

Adult is seated

On

Off

Child is seated

Off

On

Child restraint system is set

Off

On

Occupant classification system failure

Off

On

HINT:

  • The timing chart below is based on the operation of the passenger airbag ON/OFF indicator. Use the chart in order to check the indicator light circuit.
  • When the occupant classification system has trouble, both the SRS warning light and the passenger airbag ON/OFF indicator ("OFF") come on. In this case, check for DTCs in the "Airbag System" first.



3. CHECK PASSENGER AIRBAG ON/OFF INDICATOR

(a) Turn the engine switch on (IG).

(b) Check that the passenger airbag ON/OFF indicator ("ON" and "OFF") comes on for approximately 4 seconds, then goes off for approximately 2 seconds.

HINT:

Refer to the table in the previous step regarding the passenger airbag ON/OFF indicator when the engine switch is turned on (IG) and approximately 6 seconds pass.