Headlight Dimmer Switch Circuit [10/2023 - ]: Procedure

1. Using the GTS, read the Data List.

   Chassis > Steering Angle Sensor > Data List 

   Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
   Light OFF Switch	Light control switch DRL-off position signal	OFF or ON	OFF: Light control switch not in DRL-off position ON: Light control switch in DRL-off position	w/ DRL OFF Switch
   Auto Light Switch	Light control switch Auto position signal	OFF or ON	OFF: Light control switch not in Auto position ON: Light control switch in Auto position	-
   Head Light Switch (Tail)	Light control switch Tail position signal	OFF or ON	OFF: Light control switch in neither Tail nor Head position ON: Light control switch in Tail or Head position	-
   High Beam Main Switch	Headlight dimmer switch High position signal	OFF or ON	OFF: Headlight dimmer switch not in High position ON: Headlight dimmer switch in High position	-
   Passing Light Switch	Headlight dimmer switch Flash position signal	OFF or ON	OFF: Headlight dimmer switch not in Flash position ON: Headlight dimmer switch in Flash position	-

   Chassis > Steering Angle Sensor > Data List 

   Tester Display
   Light OFF Switch
   Auto Light Switch
   Head Light Switch (Tail)
   High Beam Main Switch
   Passing Light Switch

   OK

   Normal conditions listed above are displayed.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

See step  7

Result: 

OK 

See step  2

1. Using the GTS, read the Data List.

   Chassis > Steering Angle Sensor > Data List 

   Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
   Head Light Switch (Head)	Light control switch Head position signal	OFF or ON	OFF: Light control switch not in Head position ON: Light control switch in Head position	-

   Body Electrical > Main Body > Data List 

   Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
   Head Light SW (Head)	Light control switch Head position signal	OFF or ON	OFF: Light control switch not in Head position ON: Light control switch in Head position	-

   Chassis > Steering Angle Sensor > Data List 

   Tester Display
   Head Light Switch (Head)

   Body Electrical > Main Body > Data List 

   Tester Display
   Head Light SW (Head)

   OK

   Normal conditions listed above are displayed.

   Result

   Result	Proceed to
   OK	A
   NG ("Steering Angle Sensor" side abnormality)	B
   NG ("Main Body" side abnormality)	C
   NG ("Steering Angle Sensor" and "Main Body" are abnormality)	D

Result: 

A 

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [10/2023 - ] 

Result: 

B 

REPLACE STEERING SENSOR. Refer to  REMOVAL [10/2023 - ] 

Result: 

D 

See step  4

Result: 

C 

See step  3

1. Disconnect the G206 main body ECU (multiplex network body ECU) connector.
2. Disconnect the G30 steering sensor connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   G206-26 (HEAD) - G30-7 (HEAD)	Always	Below 1 Ω

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to  REMOVAL [10/2023 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

1. Remove the turn signal switch.

   Refer to REMOVAL [12/2017 - ]

2. Inspect the turn signal switch.

   Refer to INSPECTION [10/2020 - ]

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE TURN SIGNAL SWITCH. Refer to  REMOVAL [12/2017 - ] 

Result: 

OK 

See step  5

1. Remove the steering wheel switch housing.

   Refer to REMOVAL [10/2023 - ]

2. Inspect the steering wheel switch housing.

   Refer to INSPECTION [12/2017 - ]

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE STEERING WHEEL SWITCH HOUSING. Refer to  REMOVAL [10/2023 - ] 

Result: 

OK 

See step  6

1. Disconnect the G206 main body ECU (multiplex network body ECU) connector.
2. Disconnect the G30 steering sensor connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   G206-26 (HEAD) or G30-7 (HEAD) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE STEERING SENSOR. Refer to  REMOVAL [10/2023 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

1. Remove the turn signal switch.

   Refer to REMOVAL [12/2017 - ]

2. Inspect the turn signal switch.

   Refer to INSPECTION [10/2020 - ]

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE TURN SIGNAL SWITCH. Refer to  REMOVAL [12/2017 - ] 

Result: 

OK 

See step  8

1. Remove the steering wheel switch housing.

   Refer to REMOVAL [10/2023 - ]

2. Inspect the steering wheel switch housing.

   Refer to INSPECTION [12/2017 - ]

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE STEERING SENSOR. Refer to  REMOVAL [10/2023 - ] 

Result: 

NG 

REPLACE STEERING WHEEL SWITCH HOUSING. Refer to  REMOVAL [10/2023 - ]