2000 LEXUS GS400 Service Repair Manual

I04169
12
I04170
62
I04171
62
I04172
6 28
9
11
I04173
6 28
9
11
BE±178
± BODY ELECTRICALPOWER MIRROR CONTROL SYSTEM
2479 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(b) Reverse the polarity, and check that the mirror turns to the
right side.
(c) Connect the positive (+) lead from the battery to terminal
6 and the negative (±) lead to terminal 2, and check that
the mirror turns upward.
(d) Reverse the polarity, and check that the mirror turns
downward.
If operation is not as specified, replace the mirror assembly.
9. w/ Driving position memory:
INSPECT MIRROR MOTOR CIRCUIT
Left side: (See page DI±882)
Right side: (See page DI±916)
10. w/ Driving position memory only:
INSPECT MIRROR POSITION SENSORS OPERATION
HINT:
Strip off the vinyl tape of the connector and remove terminals
1, 2, 6, 8, 9, 10 and 11 from the connector housing.
(a) Connect a series of three 1.5 V dry cell batteries.
(b) Connect the positive (+) lead from the dry cell batteries to
terminal 8 and the negative (±) lead to terminal 11.
(c) Connect the positive (+) lead from the voltmeter to termi-
nal 9 and the negative (±) lead to terminal 11.
(d) Apply battery positive voltage to terminals 2 and 6, then
check that the voltage gradually changes according to the
table below while the mirror moves between the upper-
most position and lowermost position.
Mirror
positionLowermostMirror
positionUppermost
Voltage2.8 ± 5.0Changes
gradually0 ± 1.8
If voltage value is not as specified, replace the motor assembly.

I04174
2
18
10
11
I04175
2
18
10
11
I04176
SW1
SW2
SET Switch
I07732
When folded front
At drive
position
At retract position(a)
(b)
(c)
(d)
(e)
± BODY ELECTRICALPOWER MIRROR CONTROL SYSTEM
BE±179
2480 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(e) Disconnect the 4 leads of the battery and voltmeter.
(f) Connect the positive (+) lead from the voltmeter to termi-
nal 10 and negative (±) lead to terminal 11.
(g) Apply battery positive voltage to terminals 1 and 2, then
inspect that the voltage gradually changes according to
the table below while the mirror moves between the left±
most position and right±most position.
Mirror
positionLeft±mostMirror
positionRight±most
Voltage
LEFT2.8 ± 5.0Changes
gradually0 ± 1.8
Voltage
RIGHT0 ± 1.8Changes
gradually2.8 ±5.0
If voltage value is not as specified, replace the motor assembly.
11. w/ Driving position memory only:
INSPECT MIRROR POSITION SENSORS CIRCUIT
Left side: (See page DI±884)
Right side (See page DI±918)
12. INSPECT DRIVING POSITION MEMORY AND RE-
TURN SWITCH CONTINUITY
Switch positionTester connectionSpecified condition
SET switch ON1 ± 7Continuity
Return SW1 ON1 ± 3Continuity
Return SW2 ON1 ± 5Continuity
If continuity is not as specified, replace the switch.
13. INSPECT DRIVING POSITION MEMORY AND RE-
TURN SWITCH CIRCUIT (See page DI±887)
14. TAIWAN models:
INSPECT ELECTRICAL RETRACT MOTOR OPERA-
TION
(a) When folded front position:
(1) Connect the positive (+) lead from the battery to ter-
minal 1 and negative (±) lead to terminal 2, check
that the mirror operates at retract position.
(2) Reverse the polarity, check that the mirror does not
operate.
If operation is not as specified, replace the mirror assembly.
(b) Between folded front position and driving position:
(1) Connect the positive (+) lead from the battery to ter-
minal 1 and negative (±) lead to terminal 2, check
that the mirror operates at retract position.
(2) Reverse the polarity, check that the mirror operate
at folded front position.
If operation is not as specified, replace the mirror assembly.

BE±180
± BODY ELECTRICALPOWER MIRROR CONTROL SYSTEM
2481 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(c) When driving position:
(1) Connect the positive (+) lead from the battery to ter-
minal 1 and negative (±) lead to terminal 2, check
that the mirror operates at retract position.
(2) Reverse the polarity, check that the mirror does not
operate.
If operation is not as specified, replace the mirror assembly.
(d) Between driving position and retract position:
(1) Connect the positive (+) lead from the battery to ter-
minal 1 and negative (±) lead to terminal 2, check
that the mirror operates at retract position.
(2) Reverse the polarity, check that the mirror operate
at return position (Stopping at driving position).
If operation is not as specified, replace the mirror assembly.
(e) When retract position:
(1) Connect the positive (+) lead from the battery to ter-
minal 1 and negative (±) lead to terminal 2, check
that the mirror does not operates.
(2) Reverse the polarity, check that the mirror operate
at return position (Stopping at driving position).
If operation is not as specified, replace the mirror assembly.

BE0HC±06
I01369
Electro Chromic Outer Mirror
Electro Chromic Inner Mirror
Driver Side Junction Block

ECU±IG Fuse
± BODY ELECTRICALELECTRO CHROMIC MIRROR SYSTEM
BE±181
2482 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
ELECTRO CHROMIC MIRROR SYSTEM
LOCATION

BE0HD±04
I05186
ºBrightº ºDarkº1
2
3
4
Black coloured tape
I04048
Wire Harnes Side BE±182
± BODY ELECTRICALELECTRO CHROMIC MIRROR SYSTEM
2483 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. INSPECT ELECTRO CHROMIC INNER MIRROR OP-
ERATION
(a) Connect the positive (+) lead from the battery to terminal
1 and the negative (±) lead to terminal 4.
(b) Connect the positive (+) lead from the voltmeter to termi-
nal 2 and the negative (±) lead to terminal 3.
(c) Attach a black coloured tape to forward sensor to prevent
it from sensing.
(d) When the mode is turned to AUTO, check that indicator
light lights up.
(e) Light up the mirror with an electric light, and check that
there is battery positive voltage and mirror surface
changes ºbrightº to ºdarkº.
If operation is not as specified, replace the inner mirror.
2. INSPECT ELECTRO CHROMIC INNER MIRROR CIR-
CUIT
Disconnect the connector from the mirror and inspect the con-
nector on the wire harness side, as shown.
Tester connectionConditionSpecified condition
4 ± GroundConstantContinuity
1 ± GroundIgnition switch LOCK or ACCNo voltage
1 ± GroundIgnition switch ONBattery positive voltage
If circuit is not as specified, inspect the circuits connected to
other parts.

I04178
ºBrightº
ºDarkºw/o Memory
2 1
I04179
ºBrightº
ºDarkºw/ Memory
5 4
± BODY ELECTRICALELECTRO CHROMIC MIRROR SYSTEM
BE±183
2484 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
3. w/o Driving position memory:
INSPECT ELECTRO CHROMIC OUTER MIRROR OP-
ERATION
(a) Disconnect the outer mirror connector.
(b) Connect the positive (+) lead from the dry cell battery to
terminal 2 and the negative (±) lead to terminal 1, then
check that the mirror surface changes to ºdarkº.
(c) Check the mirror turns to ºbrightº after disconnecting the
battery.
If operation is not as specified, replace the mirror assembly.
4. w/ Driving position memory:
INSPECT ELECTRO CHROMIC OUTER MIRROR OP-
ERATION
(a) Disconnect the outer mirror connector.
(b) Connect the positive (+) lead from the dry cell battery to
terminal 5 and the negative (±) lead to terminal 4, then
check that the mirror surface changes to ºdarkº.
(c) Check the mirror turns to ºbrightº after disconnecting the
battery.
If operation is not as specified, replace the mirror assembly.

BE0GH±10
I01370
Ignition Switch
Seat Heater SwitchPassenger Side Junction Block
SEAT±HTR Fuse
Seat Heater CushionSeat Heater Back
Seat Heater Cushion Inner
BE±184
± BODY ELECTRICALSEAT HEATER SYSTEM
2485 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
SEAT HEATER SYSTEM
LOCATION

BE0GI±07
I04180e±6±2±H
I04181
4 6
L
R Switch
L Switch
I04182
Seat back connector ºAº
Seat cushion
inner
connector ºBº
± BODY ELECTRICALSEAT HEATER SYSTEM
BE±185
2486 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. INSPECT SEAT HEATER SWITCH CONTINUITY
Switch positionTester connectionSpecified condition
Right side3 ± 4 ± 6Continuity
OFF±No continuity
Left side2 ± 4 ± 6Continuity
Illumination circuit1 ± 5Continuity
If continuity is not as specified, replace the switch.
2. INSPECT SEAT HEATER INDICATOR LIGHT OPERA-
TION
(a) Connect the positive (+) lead from the battery to terminal
6 and the negative (±) lead to terminal 4.
(b) Push the seat heater switch Right or Left side and check
that the indicator light lights up.
If operation is not as specified, replace the switch and inspect
the circuits connected to other parts.
3. INSPECT SEAT HEATER CUSHION CONTINUITY
(a) Heat the thermostat with a light.
(b) Inspect the seat heater cushion continuity between termi-
nals, as shown.
Tester connectionConditionSpecified condition
A2 ± B1ConstantContinuity
A1 ± A2Seat heater temperature below 25 °C (77 °F)Continuity
B1 ± B2Seat heater temperature above 45 °C (113 °F)No continuity
If continuity is not as specified, replace the seat cushion pad.