High Beam Headlight Circuit [09/2014 - 03/2019]: 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.

   Body Electrical > Main Body > Active Test 

   Tester Display	Measurement Item	Control Range	Diagnostic Note
   Head Light Hi	Dimmer relay (High beam headlights)	ON/OFF	-

   Body Electrical > Main Body > Active Test 

   Tester Display
   Head Light Hi

   OK

   High beam headlights illuminate.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [09/2014 - 03/2019] 

Result: 

NG 

See step  2

1. Using a voltmeter, check the signal reading of the semiconductor pwr integration ECU.

   Refer to ON-VEHICLE INSPECTION [09/2014 - ]

   OK

   Output signal reading is normal.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

INSPECT SEMICONDUCTOR PWR INTEGRATION ECU (RESULTS OF SIGNAL READING CHECK). Refer to  PROCEDURE - Step 2 

Result: 

OK 

See step  3

1. Remove the semiconductor pwr integration ECU from the No. 2 engine room relay block and No. 2 junction block assembly.

   Refer to ON-VEHICLE INSPECTION [09/2014 - ]

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a

   Component without semiconductor pwr integration ECU connected (No. 2 Engine Room Relay Block and No. 2 Junction Block Assembly)

   -

   -

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

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   2B-1 (BATT) - Body ground	Always	11 to 14 V
   2A-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
   2D-14 (GND1) - Body ground	Always	Below 1 Ω
   2G-5 (GND2) - Body ground	Always	Below 1 Ω

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  4

1. Disconnect the O2 main body ECU (multiplex network body ECU) connector.
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   2D-2 (-S) - O2-1 (DIM)	Always	Below 1 Ω
   O2-1 (DIM) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  5

1. Replace the semiconductor pwr integration ECU with a new or known good one.

   Refer to REMOVAL [09/2014 - ]

2. Check that the high beam headlights operate normally.

   OK

   High beam headlights operate normally.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

END (SEMICONDUCTOR PWR INTEGRATION ECU WAS DEFECTIVE) 

Result: 

NG 

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to  REMOVAL [09/2014 - ]