Inspection Procedure

HINT:

• Read freeze frame data using Techstream. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
• STP signal conditions can be checked using Techstream.

1. Connect Techstream to the DLC3.
2. Turn the ignition switch ON.
3. Turn the tester ON.
4. Select the following menu items: Powertrain / Engine and ECT / Data List / Stop Light Switch.
5. Check the STP signal when the brake pedal is depressed and released.
   BRAKE PEDAL POSITION AND SIGNALS REFERENCE
   
   

   Brake Pedal Operation	Specified Conditions
   Depressed	STP signal ON
   Released	STP signal OFF

1. CHECK STOP LIGHT SWITCH ASSEMBLY (TERMINAL B VOLTAGE) 
   1. Disconnect the A3 stop light switch connector.
   Fig 1: Identifying Stop Light Switch Connector Terminals
   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. Turn the ignition switch ON.
   3. Measure the voltage between the terminals of the A3 stop light switch connector and body ground.

      Standard voltage 

      VOLTAGE SPECIFICATION
      
      

      Tester Connections	Specified Conditions
      A3-2 - Body ground	9 to 14 V
      A3-3 - Body ground	9 to 14 V

   4. Reconnect the stop light switch connector.

   NG:  Go to step  4

   OK: Go to Next Step 

2. INSPECT STOP LIGHT SWITCH ASSEMBLY 
   1. Remove the stop light switch.
      Fig 2: Identifying Stop Light Switch Assembly

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. Check the resistance.

      Standard resistance 

      RESISTANCE SPECIFICATION
      
      

      Tester Connections	Switch Positions	Specified Conditions
      1-2	Switch pin not pushed	Below 1 Ω
      	Switch pin pushed	10 kΩ or higher
      3-4	Switch pin not pushed	10 kΩ or higher
      	Switch pin pushed	Below 1 Ω

   3. Reinstall the stop light switch.

   NG: REPLACE STOP LIGHT SWITCH ASSEMBLY 

   OK: Go to Next Step 

3. CHECK ECM (STP AND ST1 - VOLTAGE) 
   1. Disconnect the A9 ECM connector.
   2. Turn the ignition switch ON.
   3. Measure the voltage between the terminals ST1- and STP of the A9 ECM connector and body ground.

      Standard voltage 

      VOLTAGE SPECIFICATION
      
      

      Tester Connections	Brake Pedal Operations	Specified Conditions
      A9-35 (ST1-) - Body ground	Released	9 to 14 V
      	Depressed	0 to 3V
      A9-36 (STP) - Body ground	Released	0 to 3V
      	Depressed	9 to 14 V

   4. Reconnect the ECM connector.
   Fig 3: Identifying Releasing And Depressing Brake Pedal
   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

   OK: REPLACE ECM 

4. INSPECT FUSE (STOP AND IGN FUSE) 
   1. Remove the STOP and IGN fuses from the instrument panel junction block.
   Fig 4: Identifying STOP And IGN Fuses
   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. Measure the resistance.

      Standard resistance: 

      Below 1 Ω 

   3. Reinstall the STOP and IGN fuses.

   NG: CHECK FOR SHORTS IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE 

   OK: REPAIR OR REPLACE HARNESS OR CONNECTOR