ACC Signal Circuit: Procedure

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON.
3. Turn the Techstream on.
4. Enter the following menus: Body Electrical / Main Body / Data List.
5. Read the display on the Techstream.
   MAIN BODY
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   ACC SW	Ignition switch ACC signal / ON or OFF	ON: Ignition switch ACC OFF: Ignition switch off	"ON" is also displayed for this item when the ignition switch is ON.

   OK

   Normal conditions listed above are displayed.

NG → See step   2 

OK → See step   4 

1. Remove the ECU-ACC fuse from the instrument panel junction block.
2. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   ECU-ACC fuse	Always	Below 1 Ω

NG → REPLACE FUSE 

OK: Go to next step 

1. Remove the ECU-ACC fuse from the instrument panel junction block.
   Fig 1: Checking Harness And Connector (ACC Power Source Circuit)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the voltage between the loading slot of the fuse and body ground.

   Standard voltage

   Tester Connection	Switch Condition	Specified Condition
   ECU-ACC fuse terminal - Body ground	Ignition switch off	Below 1 V
   	Ignition switch ACC	11 to 14 V

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → REPLACE MAIN BODY ECU (INSTRUMENT PANEL JUNCTION BLOCK)