Inspection Procedure

WARNING: This page is about a different car, the 2004 Lexus ES 330. However, it is still accessible from the selected car via links, so may be relevant.

CHECK PASSENGER SEAT BELT WARNING LIGHT
1. Check passenger seat belt warning operation.
  1. Remove the A/C control assembly with connector still connected.
  2. Ground the terminal A14-16 (PBEW) of A/C control assembly.
  3. Check that the passenger seat belt warning light lights up.
    OK: Warning light lights up.
OK: Go to step 2

NG: REPLACE CLOCK ASSY
CHECK HARNESS OR CONNECTOR (BETWEEN CLOCK ASSY AND AIRBAG SENSOR ASSY CENTER)
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step.
INSPECT FRONT SEAT INNER BELT ASSY RH
1. Check continuity.
  
  Fig 2: Inspecting Front Seat Inner Belt Assy RH Continuity
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  1. Short the terminal between terminals 1 and 3 of occupant detection sensor connector.
  2. Check the continuity in between terminals 1 and 2 of front seat inner belt assy RH.
    OK:
  Fig 3: Front Seat Inner Belt Assy RH Continuity Chart
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
NG: REPLACE FRONT SEAT INNER BELT ASSY RH

OK: Go to next step.
CHECK HARNESS OR CONNECTOR (FRONT BETWEEN SEAT INNER BELT ASSY RH AND OCCUPANT DETECTION ECU)
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step.
INSPECT OCCUPANT DETECTION ECU
1. Measure the resistance according to the value(s) in Fig 5 below.
  
  Fig 4: Measuring Occupant Detection ECU Resistance
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Standard:
  
  Fig 5: Occupant Detection ECU Resistance Chart
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the voltage according to the value(s) in Fig 4 below.
  
  Fig 6: Measuring Occupant Detection ECU Voltage
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Standard:
NG: REPLACE OCCUPANT DETECTION ECU

OK: Go to next step.
CHECK HARNESS OR CONNECTOR (BETWEEN OCCUPANT DETECTION ECU AND AIRBAG SENSOR ECU)
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: GO TO AIRBAG SYSTEM