
05-1 142
DIAGNOSTICS - LIGHTING SYSTEM 05BVQ-02
LIGHT CONTROL SWITCH CIRCUIT
CIRCUIT DESCRIPTION
This circuit detects the state of the headlight dimmer switch.
WIRING DIAGRAM
Multiplex Network
Body ECU
Driver Side Junction Block
2
R-W
1N HU
13
17
G-B
B6 TAIL
23
R-G
B6 HEAD
15
O
B6 HF
16
V
B6 A
22
G-R
B6 FFOG
C11
Combination Switch 7 14 13 8 12 11
HU T H EL HF A HL LFG BFG
OFF
Light
Tail
Control
Head
Switch
AUTO
Low
Dimmer
High
Switch
Flash
Fog OFF
Switch ON
16 17 10
W-B G-O
IE
E68120
2005 SIENNA REPAIR MANUAL (RM1163U)
Author : Date : 1325
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DIAGNOSTICS - LIGHTING SYSTEM
INSPECTION PROCEDURE
HINT:
Start the inspection from step 1 in the case of using the hand-held tester, and start from step 2 in the case
of not using the hand-held tester.
1 READ VALUE OF HAND-HELD TESTER
(a) Connect the hand-held tester to DLC3.
(b) Turn the ignition switch ON and push the hand-held tester main switch ON.
(c) Select the items below in the DATA LIST, and read the displays on the hand-held tester.
BODY NO.1:
Measurement Item/
Item Normal Condition Diagnostic Note
Display (Range)
Headlight dimmer SW ON: Headlight dimmer switch is in HI or FLASH position
DIMMER SW -
signal/ON or OFF OFF: Headlight dimmer switch is in LO position
Headlight dimmer SW ON: Headlight dimmer switch is in FLASH position
HIGH FLASHER SW -
signal/ON or OFF OFF: Headlight dimmer switch is in except FLASH position
ON: Front fog light switch is in ON position
Front fog light SW sig-
F FOG LIGHT SW when headlight dimmer switch is LOW -
nal/ON or OFF
OFF: Front fog light switch is in OFF position
Auto light SW signal/ ON: Headlight dimmer switch is in AUTO position
AUTO LIGHT SW -
ON or OFF OFF: Headlight dimmer switch is in except AUTO position
Head light control SW ON: Light control switch is in HEAD position
HEAD LIGHT SW -
signal/ON or OFF OFF: Light control switch is in except HEAD position
Taillight SW signal/ ON: Light control switch is in TAIL or HEAD position
TAIL LIGHT SW -
ON or OFF OFF: Light control switch is in OFF position
OK PROCEED TO NEXT CIRCUIT INSPECTION
SHOWN ON PROBLEM SYMPTOMS TABLE
(See page 05-1 131)
NG
2 INSPECT HEADLAMP DIMMER SWITCH ASSY
(a) Inspect headlamp dimmer switch assy (See page 65-4 ).
NG REPLACE HEADLAMP DIMMER SWITCH ASSY
OK
2005 SIENNA REPAIR MANUAL (RM1163U)
Author : Date : 1326
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DIAGNOSTICS - LIGHTING SYSTEM
3 INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSY
(a) Measure voltage between the each of terminals as shown in the chart below.
Standard:
Tester connection Condition Specified voltage
1N-2 - Body ground Headlamp dimmer switch LOW HIGH 10 to 14 V Below 1 V
B6-15 - Body ground Headlamp dimmer switch LOW FLASH 10 to 14 V Below 1 V
B6-16 - Body ground Light control switch OFF AUTO 10 to 14 V Below 1 V
B6-17 - Body ground Light control switch OFF TAIL 10 to 14 V Below 1 V
B6-22 - Body ground Fog lamp switch OFF ON 10 to 14 V Below 1 V
B6-23 - Body ground Light control switch OFF HEAD 10 to 14 V Below 1 V
Instrument Panel Junction Block Assy
Front Side:
1N
E67348
2005 SIENNA REPAIR MANUAL (RM1163U)
Author : Date : 1327
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DIAGNOSTICS - LIGHTING SYSTEM
Instrument Panel Junction Block Assy B6
Back Side:
E67349
NG REPAIR OR REPLACE HARNESS OR
CONNECTOR
OK
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOMS TABLE
(See page 05-1 131)
2005 SIENNA REPAIR MANUAL (RM1163U)
Author : Date : 1328