Taillight Relay Circuit: Procedure

1. Connect the Techstream to the DLC3.
2. Turn the power switch on (IG).
3. Turn the Techstream on.
4. Enter the following menus: Body Electrical / Main Body / Active Test.
5. According to the display on the Techstream, perform the Active Test.
   MAIN BODY
   
   

   Techstream Display	Test Part	Control Range	Diagnostic Note
   Taillight Relay	Taillight relay	OFF or ON	-

   OK

   TAIL relay operates. (Clearance lights, taillights and license plate lights illuminate.)

NG → See step   2 

OK → See step   6 

1. Disconnect the 3A instrument panel junction block assembly connector.
2. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   3A-1 - Body ground	Power switch off	11 to 14 V

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Replace the main body ECU (multiplex network body ECU). Refer to REMOVAL .

NEXT: Go to next step 

1. Connect the Techstream to the DLC3.
2. Turn the power switch on (IG).
3. Turn the Techstream on.
4. Enter the following menus: Body Electrical / Main Body / Active Test.
5. According to the display on the Techstream, perform the Active Test.
   MAIN BODY
   
   

   Techstream Display	Test Part	Control Range	Diagnostic Note
   Taillight Relay	Taillight relay	OFF or ON	-

   OK

   TAIL relay operates. (Clearance lights, taillights and license plate lights illuminate.)

NG → See step   5 

OK → END (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) WAS DEFECTIVE)