Ignition Switch Circuit: Procedure

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch on (IG).
3. Turn the Techstream on.
4. Enter the following menus: Body Electrical / Body / Data List.
5. Read the display on the Techstream.
   BODY (BODY ECU)
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   ACC SW	ACC SW signal / ON or OFF	ON: Ignition switch on (IG or ACC) OFF: Ignition switch off	-
   IG SW	IG SW signal / ON or OFF	ON: Ignition switch on (IG) OFF: Ignition switch off	-

   OK

   Normal conditions listed above are displayed.

NG → See step   2 

OK → PROCEED TO  PROBLEM SYMPTOMS TABLE  NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE 

1. Inspect ACC relay continuity.
   Fig 1: Identifying ACC Relay Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. Remove the ACC relay from the instrument panel J/B.
   2. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection	Specified Condition
      3 - 5	10 kΩ or higher
      3 - 5	Below 1 Ω (When battery voltage is applied to terminal 1 - 2)

2. Inspect IG1 relay continuity.
   Fig 2: Identifying IG1 Relay Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. Remove the IG1 relay from the instrument panel J/B.
   2. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection	Specified Condition
      3 - 5	10 kΩ or higher
      3 - 5	Below 1 Ω (When battery voltage is applied to terminal 1 - 2)

NG → REPLACE RELAY 

OK: Go to next step 

1. Measure the voltage according to the value(s) in the table below.
   Fig 3: Identifying A1 Battery And Instrument Panel Junction Block Assembly Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard voltage

   Tester Connection	Condition	Specified Condition
   IA-1 - Body ground	Always	10 to 14 V

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Measure the voltage according to the value(s) in the table below.
   Fig 4: Identifying Instrument Panel Junction Block Assembly Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard voltage

   Tester Connection	Condition	Specified Condition
   II-4 - Body ground	Always	10 to 14 V

NG → REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 

OK: Go to next step 

1. Disconnect the connector IF from the instrument panel junction block assembly.
2. Measure the resistance according to the value(s) in the table below.
   Fig 5: Identifying Instrument Panel Junction Block Assembly (Body Ground) Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard resistance

   Tester Connection	Condition	Specified Condition
   IF-10 - Body ground	Always	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Inspect the harness and connectors related to ignition switch, referring to the wiring diagram.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → PROCEED TO  PROBLEM SYMPTOMS TABLE  NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE