Inspection Procedure

1. CHECK STOP LIGHT SWITCH OPERATION 
   1. Check that the stop light comes on when the brake pedal is depressed, and goes off when the brake pedal is released.

      OK: 

      Stop light switch function is normal. 

   1. NG: Go to step   4 

      HINT:

      Check the stop light bulb as it may have burnt out.

   2. OK: GO TO NEXT STEP 
2. INSPECT SKID CONTROL ECU (STP TERMINAL VOLTAGE) 
   1. Disconnect the skid control ECU connector.
   2. Measure the voltage according to the value(s) in the table below.

      Standard: 

      TESTER CONNECTION, CONDITION AND SPECIFIED CONDITION (1 OF 2)
      
      

      Tester Connection	Condition	Specified Condition
      S28-7(STP)- Body ground	Stop light switch ON (Brake pedal depressed)	8 to 14 V
      S28-7 (STP) & Body ground	Stop light switch OFF (Brake pedal released)	Below 1.5 V

      Fig 1: Identifying Skid Control ECU STP Terminal

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard: 

      TESTER CONNECTION, CONDITION AND SPECIFIED CONDITION (2 OF 2)
      
      

      OK: (When troubleshooting in accordance with the DTC CHART.)	A
      OK: (When troubleshooting in accordance with the PROBLEM SYMPTOMS TABLE.)	B
      NG	C

   1. B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN  PROBLEM SYMPTOMS TABLE  
   2. C: REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT) 
   3. A: GO TO NEXT STEP 
3. RECONFIRM DTC 
   1. Clear the DTC (see DTC CHECK/CLEAR  ).
   2. Check if the same DTC is detected (see DTC CHECK/CLEAR  ).

      HINT:

      Reinstall the sensors, connectors, etc. and restore the previous vehicle conditions before rechecking for DTCs.

      Result: 

      RESULT DESCRIPTION
      
      

      DTC is output	A
      DTC is not output	B

   1. B:END 
   2. A:REPLACE MASTER CYLINDER SOLENOID (SEE  OVERHAUL  ) 
4. INSPECT STOP LIGHT SWITCH ASSY (POWER SOURCE TERMINAL VOLTAGE) 
   1. Disconnect the stop light switch connector.
   2. Measure the voltage according to the value(s) in the table below.

      Standard: 

      TESTER CONNECTION, CONDITION AND SPECIFIED CONDITION (1 OF 2)
      
      

      Tester Connection	Condition	Specified Condition
      S12-2 - Body ground	Always	10 to 14 V

      Fig 2: Identifying Stop Light Switch Assy Power Source Terminals

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT) 
   2. OK: GO TO NEXT STEP 
5. INSPECT STOP LIGHT SWITCH ASSY 
   1. Measure the resistance according to the value(s) in the table below.

      Standard: 

      TESTER CONNECTION, CONDITION AND SPECIFIED CONDITION (2 OF 2)
      
      

      Tester Connection	Condition	Specified Condition
      S12-1-S12-2	Switch pin free	Below 1 Ω
      S12-1 - S12-2	Switch pin pushed in	10 kΩ or higher

      Fig 3: Inspecting Stop Light Switch Assy

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. NG: REPLACE STOP LIGHT SWITCH ASSY 
   2. OK: GO TO NEXT STEP 
6. INSPECT STOP LIGHT OPERATION RELAY 
   1. Remove the stop light operation relay.
   2. Measure the resistance according to the value(s) in the table below.

      Standard: 

      TESTER CONNECTION AND SPECIFIED CONDITION (1 OF 2)
      
      

      Tester Connection	Specified Condition
      3-4	Below 1 Ω

      Fig 4: Inspecting Stop Light Operation Relay

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. NG: REPLACE STOP LIGHT OPERATION RELAY 
   2. OK: GO TO NEXT STEP 
7. CHECK HARNESS AND CONNECTOR (BETWEEN SKID CONTROL ECU AND STOP LIGHT SWITCH) ( HOW TO PROCEED WITH TROUBLESHOOTING  ) 
   1. Disconnect the skid control ECU connector.
   2. Measure the resistance according to the value(s) in the table below.

      Standard: 

      TESTER CONNECTION AND SPECIFIED CONDITION (2 OF 2)
      
      

      Tester Connection	Specified Condition
      S28-7 (STP) - S12-1	Below 1 Ω
      S28-7 (STP) - Body ground	10 kΩ or higher

      Fig 5: Identifying Connectors (Skid Control ECU And Stop Light Switch)

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
   2. OK: REPLACE MASTER CYLINDER SOLENOID (SEE  OVERHAUL  ) 

HINT:

• When troubleshooting in accordance with the DTC CHART, check DTCs before replacing the master cylinder solenoid (see DTC CHECK/CLEAR  ).
• When troubleshooting in accordance with the PROBLEM SYMPTOMS TABLE, be sure to follow the table before replacing the master cylinder solenoid (see PROBLEM SYMPTOMS TABLE  ).