LEXUS GS400 2000 Service Repair Manual

BE0GS±10
I01362
Defogger WireIgnition SwitchDefogger Switch
Defogger Switch
Mirror Assembly

Mirror Defogger
LEXUS navigation
System
Passenger Side
Junction Block

DEF M±Fuse

MIR HTR Fuse

Mirror Defogger Relay
Mirror Assembly

Mirror Defogger
Passenger Cowl Side
Relay Block

Defogger Relay
± BODY ELECTRICALDEFOGGER SYSTEM
BE±107
2408 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
DEFOGGER SYSTEM
LOCATION

BE0GT±03
I04112
6
I04113
I04114
Wire Harness Side
Connector ºAº Connector ºBº
I01200
2 1
35
2 5
1 3
BE±108
± BODY ELECTRICALDEFOGGER SYSTEM
2409 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. INSPECT DEFOGGER TIMER OPERATION
(a) Connect the positive (+) lead from the voltmeter to termi-
nal 6 of body ECU No.1 connector and negative (±) lead
to body ground.
(b) When the switch is OFF, the voltage should be approx.
12V.
(c) Turn the defogger switch ON and check that the indicator
lights up and that the voltage is less than 1 V.
(d) After 15 minutes, check that the switch is OFF and the
voltage is approx. 12 V.
If operation is not as specified, replace the switch.
2. INSPECT DEFOGGER SWITCH (in PANEL SWITCH)
CIRCUIT
Connector disconnected:
Disconnect the connector from the panel switch and inspect the
connector on wire harness side, as shown in the chart.
Tester connectionConditionSpecified condition
B10 ± GroundConstantContinuity
A1 ± GroundConstantBattery voltage
A2 ± GroundIgnition switch LOCKNo voltage
A2 ± GroundIgnition switch ACC or ONBattery voltage
If the circuit is not as specified, replace the switch.
3. INSPECT DEFOGGER RELAY CONTINUITY
ConditionTester connectionSpecified condition
Constant1 ± 2Continuity
Apply B+ between
terminals 1 and 2.3 ± 5Continuity
If continuity is not as specified, replace the relay.
4. INSPECT DEFOGGER RELAY CIRCUIT
(See page DI±812 and BE±21)

I01200
2 1
35
2 5
1 3
I01291
Tester Probe
Tin FoilHeat Wire
I01292
At Center
I01293
0 Volts
Broken
WireSeveral
Volts
Battery
side Ground sideFoil strip


± BODY ELECTRICALDEFOGGER SYSTEM
BE±109
2410 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
5. INSPECT MIRROR DEFOGGER RELAY CONTINUITY
ConditionTester connectionSpecified condition
Constant1 ± 2Continuity
Apply B+ between
terminals 1 and 2.3 ± 5Continuity
If continuity is not as specified, replace the relay.
6. INSPECT MIRROR DEFOGGER RELAY CIRCUIT
(See page BE±21)
7. INSPECT DEFOGGER WIRE
NOTICE:

When cleaning the glass, use a soft, dry cloth, and wipe the
glass in the direction of the wire. Take care not to damage
the wires.

Do not use detergents or glass cleaners with abrasive in-
gredients.

When measuring voltage, wrap a piece of tin foil around the
tip of the negative probe and press the foil against the wire
with your finger, as shown.
(a) Turn the ignition switch ON.
(b) Turn the defogger switch ON.
(c) Inspect the voltage at the center of each heat wire, as
shown.
VoltageCriteria
Approx. 5VOkay (No break in wire)
Approx. 10V or 0VBroken wire
HINT:
If there is approximately 10 V, the wire is broken between the
center of the wire and the positive (+) end. If there is no voltage,
the wire is broken between the center of the wire and ground.
(d) Place the voltmeter positive (+) lead against the defogger
wire on the battery side.
(e) Place the voltmeter negative (±) lead with the foil strip
against the wire on the ground side.
(f) Slide the positive (+) lead from battery to ground side.
(g) The point where the voltmeter deflects from several V to
zero V is the place where the defogger wire is broken.
HINT:
If the heat wire is not broken, the voltmeter indicates 0 V at the
positive (+) end of the heat wire but gradually increases to about
12 V as the meter probe moves to the other end.

I01294
Repair Point
Broken
Wire
Marking Tape
I01295
I04115
78
I04269
12 13
BE±110
± BODY ELECTRICALDEFOGGER SYSTEM
2411 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
8. IF NECESSARY, REPAIR DEFOGGER WIRE
(a) Clean the broken wire tips with grease, wax and silicone
remover.
(b) Place the masking tape along both sides of the wire for
repair.
(c) Thoroughly mix the repair agent (Dupont paste No.
4817).
(d) Using a fine tip brush, apply a small amount of the agent
to the wire.
(e) After a few minutes, remove the masking tape.
(f) Do not repair the defogger wire for at least 24 hours.
9. w/ Mirror heater (w/o Driving position memory):
INSPECT MIRROR DEFOGGER OPERATION
(a) Connect the positive (+) lead from the battery to terminal
7 and the negative (±) lead to terminal 8.
(b) Check that the mirror becomes warm.
HINT:
It will take a short time for the mirror to become warm.
10. w/ Mirror heater (w/ Driving position memory):
INSPECT MIRROR DEFOGGER OPERATION
(a) Connect the positive (+) lead from the battery to terminal
12 and the negative (±) lead to terminal 13.
(b) Check that the mirror becomes warm.
HINT:
It will take a short time for the mirror to become warm.

BE02C±02
± BODY ELECTRICALPOWER WINDOW CONTROL SYSTEM
BE±111
2412 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
POWER WINDOW CONTROL SYSTEM
TROUBLESHOOTING
1. WINDOW DOES NOT OPERATE WITH POWER WINDOW MASTER SWITCH. (MANUAL OR AU-
TOMATIC OPERATION CAN NOT BE PERFORMED.)
TroubleSuspect Area (terminal No.)Parts name
All windows do not operate with master
switch of each window.
PWS terminal of body ECU does not output sig-
nal.

Body ECU PWS terminal (B8) output

Master Switch PW terminal (15) output

Check wire harness between PWS terminal
and PW terminal (15)

Body ECU

Master switch
Windows except driver's do not operate
with master switch of each window.
Master switch (window lock circuit) faulty

Check continuity between master switch PW
terminal (15) and W/L2 terminal (10)

Check wire harness between W/L2 terminal of
master switch (10) and PCT terminals of each
power window switch.

Master switch
Only specific window does not operate.
(Manual and automatic operation can not
be performed.)
FLOW CHART <A>±
Only specific window does not operate.
(Automatic operation can not be per-
formed.)When ºJam Protectionº sensor is defective, auto-
matic function as a fail±safe function might be
unable.
Master switch

Power window switch

Door control ECU

Only specific window does not operate. (Neither manual nor automatic operation is available.)1
Diagnosis check:
Check output diagnosis trouble codes 21 ± 26 when operating the
master switch and power window switch.
(Refer to ºMultiplex Communication Systemº)If the door lock of the applicable seat operates.
Wire harness faulty or
D FR DOOR fuse faulty.
No Yes
Disconnect the driver door control ECU connector.
Ye sNo
Voltage check:
With ignition switch ON if 10 to 14 V power is
supplied to PCT (3) of power window switch.Wire harness faulty.
(Between master switch W/L2 terminal
(10) and power window switch PCT
terminal (3)
Continuity check:
Master switch faulty.
Check continuity master switch and power window switch.No (Driver side)
No (Except driver side)Ye s
No Ye s
Wire harness check:
Master switch
Master switch Driver door control ECU
AUTO (7)
DDN (18)
DUP (6)AUTO (B6)
MDN (B4)
MUP (B5)
Power window switch
Power window switch Driver door control ECU
A (5)
D (4)
U (6)AUTO (A22)
MDN (A23)
MUP (A24)
Wire harness faulty.
Continuity check:
Check continuity between UP terminal (A2) and
GND terminal (C12), DN terminal (A11) and
GND terminal (C12) of driver door control ECU .
Ye s
When replacing with the normal driver door control ECU
removed from another seat, if it operates normally.
Driver door control ECU faulty.No Yes
Driver door control ECU faulty.
No
Power window motor check:
Disconnect the motor connector.
Connect the battery positive (+) lead to terminal
UP (2) and negative (±) lead to terminal DN
(1) of wire harness side motor connector, check that
the motor operates.
Check power window motor.Ye s
No
Wire harness faulty.
Ye s
Power window motor faulty.
No
BE±112
± BODY ELECTRICALPOWER WINDOW CONTROL SYSTEM
2413 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
FLOW CHART <A>

± BODY ELECTRICALPOWER WINDOW CONTROL SYSTEM
BE±113
2414 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
2. REMOTE CONTROL OF ALL WINDOWS (EXCEPT DRIVER'S) DOES NOT FUNCTION WITH MAS-
TER SWITCH. (WINDOWS OPERATE NORMALLY WITH EACH OF MASTER SWITCHES.
TroubleSuspect Area (terminal No.)Parts name
All windows (except driver's) do not oper-
ate by remote control.
Fail±safe mode caused by leaving the master
switch ON or short circuit occurred in remote
control control switch of master switch.

Check continuity of master switch.

Master switch
Only passenger's door does not operate.
(UP, DOWN and AUTO DOWN do not op-
erate.)
Driver door control ECU DT1 terminal does not
output.

Driver door control ECU DT1 terminal (B3)

Master switch DT1 terminal (3)

Check wire harness between terminal DT1 (B3)
and DT1 (3)

Driver door control ECU

Master switch
Only passenger's door does not operate.
(Each operation does not operate.)Master switch faulty

Check continuity of master switch.
Only rear right side door does not operate.
(UP, DOWN and AUTO DOWN do not op-
erate.)
Driver door control ECU DT2 terminal does not
output.

Driver door control ECU DT2 terminal (B2)

Master switch DT2 terminal (11)

Check wire harness between terminal DT2 (B2)
and DT2 (11)

Driver door control ECU

Master switch
Only rear right side door does not operate.
(Either UP, DOWN or AUTO DOWN does
not operate.)Master switch faulty

Check continuity of master switch.
Only rear left side door does not operate.
(UP, DOWN and AUTO DOWN do not op-
erate.)
Driver door control ECU DT3 terminal does not
output.

Driver door control ECU DT3 terminal (B1)

Master switch DT3 terminal (14)

Check wire harness between terminal DT3 (B1)
and DT3 (14)

Driver door control ECU

Master switch
Only rear left side door does not operate.
(Either UP, DOWN or AUTO DOWN does
not operate.)Master switch faulty

Check continuity of master switch.
Driver door control ECU

Master switch
Only UP operation does not operate.
(All window (Except driver side) doors.)
Master switch ON SC2 terminal does not output.
Driver door control ECU SC2 terminal does not
input.

Master switch SC2 terminal (12)

Driver door control ECU SC2 terminal (B10)

Check wire harness between terminal SC2 (12)
and SC2 (B10)

Driver door control ECU

Master switch
Only UP operation does not operate.
(Only specific window does not operate.)Master switch faulty

Check continuity of master switch.
Only DOWN operation does not operate.
(All window (Except driver side) doors.)
Master switch ON SC1 terminal does not output.
Driver door control ECU SC1 terminal does not
input.

Master switch SC1 terminal (4)

Driver door control ECU SC1 terminal (B9)

Check wire harness between terminal SC1 (4)
and SC1 (B9)

Driver door control ECU

Master switch
Only DOWN operation does not operate.
(Only specific window does not operate.)Master switch faulty

Check continuity of master switch.

BE±114
± BODY ELECTRICALPOWER WINDOW CONTROL SYSTEM
2415 Author: Date:
2000 LEXUS GS300/GS400 (RM718U) Only AUTO DOWN operation does not
operate.
(All window (Except driver side) doors.)
Master switch ON SC3 terminal does not output.
Driver door control ECU SC3 terminal does not
input.

Master switch SC3 terminal (13)

Driver door control ECU SC3 terminal (B11)

Check wire harness between terminal SC3 (13)
and SC3 (B11)

Driver door control ECU

Master switch
Only AUTO DOWN operation does not
operate.
(Only specific window does not operate.)Master switch faulty

Check continuity of master switch.
3. THE KEY RELATED POWER WINDOW OPERATION DOES NOT OPERATE WITH DRIVER SIDE
DOOR KEY CYLINDER. (MASTER SWITCH OPERATION IS NORMAL.)
TroubleSuspect Area (terminal No.)Parts name
Door lock system does not operate with
door key.Refer to ºPOWER DOOR LOCK CONTROL
SYSTEMº.±
Door lock system does not operate with
door key.
Fail±safe mode caused by error on jam protec-
tion sensor of power window.
(Operation of power window with multi±function
transmitter is prohibited.)
HINT: DTC 31 ± 38 output
Refer to ºMultiplex Communication Systemº.
4. POWER WINDOW DOES NOT OPERATE WITH MULTI±FUNCTION TRANSMITTER. (WINDOWS
OPERATE NORMALLY WITH MASTER SWITCH.)
TroubleSuspect Area (terminal No.)Parts name
Door lock and luggage compartment
opener do not operate with multi±function
transmitter.Refer to ºWIRELESS DOOR LOCK CONTROL
SYSTEMº.±
Only luggage compartment opener oper-
ates with multi±function transmitter.Wireless door lock transmitter faulty.Check wireless door lock transmitter.
Door lock and luggage compartment
opener operate with multi±function trans-
mitter.
Fail±safe mode caused by error on jam protec-
tion sensor of power window.
(Operation of power window with multi±function
transmitter is prohibited.)
HINT: DTC 31 ± 38 output
Refer to ºMultiplex Communication Systemº.
5. WINDOW MOVES DOWN WITHOUT BEING ORDERED DURING THE UP OPERATION
TroubleSuspect Area (terminal No.)Parts name
After the window is fully closed, it starts to
move down.
Power window motor limit switch wire harness
faulty.

Power window motor reset switch is reset.

Driver door control ECU LMT terminal (B12)

Driver door control ECU
The window moves down during the up
operation.FLOW CHART <B>±

The window moves down during the up operation.2
With ignition switch ON, when performing the auto±up or manual ±up
operation, if the factor which increases the sliding resistance of window
glass near the inverse position is recognized.
Disassemble the door and replace or repair the
component.
Reset the limit switch.
If power window regulator and motor operate smoothly.
Ye s
No
Check or repair door glass run and window guide
frame.
Replace the driver door control ECU with the normal one
removed from another seat. Sliding resistance check:
Power window motor reset:
Check operation power window control is normal.
Remove power window regulator assembly.
When raising the assembled window glass by hand if the glass slides
smoothly without being caught.
Ye s Sliding resistance check:
Unit check:
Install power window regulator and reset the limit switch.
Power window motor reset:
Check operation power window control is normal.
Power window motor faulty.
Ye s
NoNormal.
(After checking the operation repeatedly, perform the
function check.)
No
Driver door control ECU faulty.Ye s
No
HINT: When difference of descending time comparing
to the opposite window is recognized, there seems to
be an error on sliding components (door glass run
and window regulator.)
± BODY ELECTRICALPOWER WINDOW CONTROL SYSTEM
BE±115
2416 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
FLOW CHART <B>

BE0HE±10
I01363
Driver side Junction Block

Body ECU No.2
Ignition SwitchPower Window Switch
Power Window Master Switch
Power Window Motor
Power Window Motor
Power Window Switch Power Window Switch
Passenger side Junction Block

Body ECU No.1
BE±116
± BODY ELECTRICALPOWER WINDOW CONTROL SYSTEM
2417 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
LOCATION