2004 Scion xA StandardFACTORY OEM SERVICE PROCEDURE

Inspection Procedure

  1. CHECK OPERATION OF STOP LIGHT 
    1. Check if the stop lights go on and off normally when the brake pedal is depressed and released.
    1. NG : REPAIR OR REPLACE STOP LAMP SWITCH CIRCUIT 
    2. OK : Go to next step. 
  2. READ VALUE OF HAND-HELD TESTER OR OBD II SCAN TOOL (STP SIGNAL) 
    1. Turn the ignition switch ON.
    2. Select the item "DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / STOP LIGHT SW" and read its value displayed on the hand-held tester or OBD II scan tool.

      Standard: 

      STANDARD

      Brake Pedal Specified Condition
      Depressed STP Signal ON
      Released STP Signal OFF
      Fig 1: Pressing Brake Pedal
      G03367247Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. OK : CHECK FOR INTERMITTENT PROBLEMS (See  CHECK FOR INTERMITTENT PROBLEMS  ) 
    2. NG : Go to next step. 
  3. INSPECT STOP LAMP SWITCH ASSY 
    Fig 2: Inspecting Stop Lamp Switch Assy
    G03367248Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Measure the resistance between terminals when the switch is ON and OFF.

      Standard: 

      STANDARD

      Switch Position Tester Connection Specified Condition
      ON (Free) 1 - 2 Below 1 Ω
      OFF (Pushed In) 10 kΩ Or Higher
    1. NG : REPLACE STOP LAMP SWITCH ASSY 
    2. OK : Go to next step. 
  4. CHECK HARNESS AND CONNECTOR (STOP LAMP SWITCH - ECM) 
    Fig 3: Checking Harness (Stop Lamp Switch - ECM)
    G03367249Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the S6 stop lamp switch connector.
    2. Disconnect the E5 ECM connector.
    3. Measure the resistance between the wire harness side connectors.

      Standard (Check for open): 

      STANDARD (CHECK FOR OPEN)

      Tester Connection Specified Condition
      Stop Lamp Switch (S6-1) - STP (E5-19) Below 1 Ω

      Standard (Check for short): 

      STANDARD (CHECK FOR SHORT)

      Tester Connection Specified Condition
      Stop Lamp Switch (S6-1) Or STP (E5-19) - Body Ground 10 kΩ Or Higher
    4. Reconnect the stop lamp switch connector.
      5. Fig 4: Checking Connector (Stop Lamp Switch - ECM)
      G03367250Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Reconnect the ECM connector.
    1. NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. OK : REPLACE ECM (See  REPLACEMENT  ) 
Chapter Navigation
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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.