IG Signal Circuit [10/2014 - ]: Procedure

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

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

   OK

   Normal conditions listed above are displayed.

Result: 

OK 

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE 

(Refer to PROBLEM SYMPTOMS TABLE [10/2014 - ] )

Result: 

NG 

See step  2

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

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   3E-1 - Body ground	Always	11 to 14 V

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  3

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

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   3A-29 - Body ground	Engine switch on (IG)	11 to 14 V
   3A-29 - Body ground	Engine switch off	Below 1 V

Result: 

NG 

GO TO SMART KEY SYSTEM (for Start Function) 

(Refer to HOW TO PROCEED WITH TROUBLESHOOTING [10/2014 - 10/2015] or HOW TO PROCEED WITH TROUBLESHOOTING [10/2015 - ] )

Result: 

OK 

See step  4

1. Remove the instrument panel junction block assembly (Refer to REMOVAL [10/2014 - ] ).
2. Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.
3. Measure the resistance according to the value(s) in the table below.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   TEXT IN ILLUSTRATION
   
   

   *a

   Component without harness connected (Instrument Panel Junction Block Assembly)

   -

   -

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   3E-1 - MB-32 (IG)	Battery not connected to 3A-29 and 3B-7	10 kΩ or higher
   3E-1 - MB-32 (IG)	Battery positive (+) → 3A-29 Battery negative (-) → 3B-7	Below 1 Ω

Result: 

OK 

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) 

(Refer to REMOVAL [10/2014 - ] )

Result: 

NG 

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 

(Refer to REMOVAL [10/2014 - ] )