Inspection Procedure

1. Check that the stop lights come on while the brake pedal is depressed, and go off when the brake pedal is released.

   OK 

   STOP LIGHT SWITCH OPERATION
   
   

   Brake Pedal Condition	Stop Light Condition
   Depressed	ON
   Released	OFF

NG: INSPECT STOP LIGHT SWITCH CIRCUIT 

OK: GO TO NEXT STEP 

1. Disconnect the stop light switch assembly connector.
2. Measure the resistance.

   Standard resistance 

   STOP LIGHT SWITCH ASSEMBLY
   
   

   Tester Connection	Switch Condition	Stop Light Condition
   1-2	Switch pin free (Brake pedal depressed)	Below 1Ω
   3-4	Switch pin free (Brake pedal depressed)	10 kΩ or higher
   1-2	Switch pin pushed in (Brake pedal released)	10 kΩ or higher
   3-4	Switch pin pushed in (Brake pedal released)	Below 1Ω

   Fig 1: Inspecting Stop Light Switch Assembly

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Reconnect the stop light switch assembly connector.

NG: REPLACE STOP LIGHT SWITCH ASSEMBLY 

OK: GO TO NEXT STEP 

1. Disconnect the A21 ECM connector.
2. Turn the ignition switch to the ON position.
3. Measure the voltage.

   Standard voltage 

   ECM (STP SIGNAL)
   
   

   Tester Connection	Brake Pedal Condition	Specified Condition
   STP (A21-36)-Body ground	Depressed	10 to 14 V
   STP (A21-36)-Body ground	Released	Below 1V
   ST1-(A21-35)-Body ground	Depressed	Below 1V
   ST1-(A21-35)-Body ground	Released	10 to 14 V

   Fig 2: Inspecting ECM (STP Signal)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
4. Reconnect the ECM connector.

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - ECM) 

OK: REPLACE ECM