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 HEATER CONTROL HOUSING SUB-ASSY (SECURITY INDICATOR LIGHT)
1. Apply about 5 V positive voltage between positive (+) lead to terminal LP (A14-10) and negative (-) lead to terminal GND (A15-21) of the heater control housing sub-assy.
  Standard: Security indicator light comes on
  NOTE:
  - If the positive (+) lead and the negative (-) lead are incorrectly connoted, the indicator light does not light up.
  - Voltage of 5 V or more will damage the indicator light.
  - If the voltage is too low, the light does not light up.
  Fig 1: Identifying Heater Control Housing Connector Terminals
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  NG: REPLACE HEATER CONTROL HOUSING SUB-ASSY (See OVERHAUL )
  
  OK: Go to next step.
CHECK WIRE HARNESS (THEFT WARNING ECU ASSY - HEATER CONTROL HOUSING SUB-ASSY)
1. Disconnect the theft warning ECU assy and A14 heater control housing sub-assy connectors.
2. Check the continuity between the theft warning ECU assy connector and heater control housing sub-assy connector, as shown in Fig 2 and Fig 3.
  
  Fig 2: Identifying Theft Warning ECU Assy And Heater Control Housing Sub-Assy Connector
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Standard:
  
  Fig 3: Theft Warning ECU Assy And Heater Control Housing Sub-Assy Connector Continuity Specification Chart
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  NG: REPAIR OR REPLACE WIRE HARNESS AND CONNECTOR
  
  OK: Go to next step.
CHECK WIRE HARNESS (HEATER CONTROL HOUSING SUB-ASSY - BODY GROUND)
1. Disconnect the A15 heater control housing sub-assy connector.
2. Check the continuity between the A15 heater control housing sub-assy connector and the body ground, as shown in Fig 4 and Fig 5.
  
  Fig 4: Identifying A15 Heater Control Housing Sub-Assy Connectors
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Standard:
  
  Fig 5: A15 Heater Control Housing Sub-Assy Connector And Body Ground Continuity Specification Chart
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  NG: REPAIR OR REPLACE WIRE HARNESS AND CONNECTOR
  
  OK: CHECK AND REPLACE THEFT WARNING ECU ASSY (See ELECTRONIC CIRCUIT INSPECTION PROCEDURE )