High Beam Headlight Circuit [10/2015 - ]: 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 / Active Test.
5. Perform the Active Test according to the display on the Techstream.
   MAIN BODY
   
   

   Tester Display	Test Part	Control Range	Diagnostic Note
   Head Light Hi	High beam headlights	ON/OFF	-

   OK

   The high beam headlights illuminate.

Result: 

OK 

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE 

(Refer to PROBLEM SYMPTOMS TABLE [10/2015 - ] )

Result: 

NG 

See step  2

1. Using a voltmeter, check the signal reading of the engine room junction block assembly (Refer to ON-VEHICLE INSPECTION [10/2015 - ] ).

   OK

   Output signal reading is normal.

Result: 

NG 

INSPECT ENGINE ROOM JUNCTION BLOCK ASSEMBLY (RESULTS OF SIGNAL READING CHECK) 

(Refer to ON-VEHICLE INSPECTION [10/2015 - ] )

Result: 

OK 

See step  3

1. Remove the engine room junction block assembly from the engine room relay block and junction block assembly.

   Refer to REMOVAL [10/2014 - ]

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a

   Component without engine room junction block assembly connected (Engine Room Relay Block and Junction Block Assembly)

   -

   -

2. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   A-1 (BATT) - Body ground	Always	11 to 14 V
   B-1 (ALT) - Body ground	Always	11 to 14 V

3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   1F-3 (GND1) - Body ground	Always	Below 1 Ω
   1G-4 (GND2) - Body ground	Always	10 kΩ or higher

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  4

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   1F-5 (DIMS) - 3D-39	Always	Below 1 Ω
   1F-5 (DIMS) or 3D-39 - Body ground	Always	10 kΩ or higher

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  5

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.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Component without harness connected (Instrument Panel Junction Block Assembly)

3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   3D-39 - MB-26 (DIM)	Always	Below 1 Ω

Result: 

NG 

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 

(Refer to REMOVAL [10/2014 - ] )

Result: 

OK 

See step  6

1. Replace the engine room junction block assembly with a new or known good one (Refer to REMOVAL [10/2014 - ] ).
2. Check that the high beam headlights operate normally.

   OK

   The high beam headlights operate normally.

Result: 

OK 

END (ENGINE ROOM JUNCTION BLOCK ASSEMBLY WAS DEFECTIVE) 

Result: 

NG 

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) 

(Refer to REMOVAL [10/2014 - ] )