1991 LEXUS SC400 key battery

3. INSPECT KEY INTERLOCK SOLENOID
(a) Disconnect the solenoid connector.
(b) Usin g an oh mme te r, me a su re th e re sista n ce be twe e nterminals 7 and 8.
Standard resistance:
12±17

If resistance value is not as specified, replace the solenoid.
(c) Touch the solenoid with your finger and check that solenoid operation can be felt when battery positive voltage.
If solenoid operation is not as specified, replace the solenoid.
4. INSPECT SHIFT LOCK CONTROL SWITCH Inspect that there is continuity between each terminal.
±
A304E (1UZ±FE) AUTOMATIC TRANSMISSION SHIFT LOCK SYSTEMAT±29
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(b) Press the mirror switch and check if the mirrors surfacerepeatedly becomes ºbrightº and ºdarkº.
If operation is not as specified, replace the liquid crystal inner
mirror.
(Circuit)
Disconnect the inner mirror connector and inspect the con-
nector on the wire harness side as shown.
Check forTester connectionConditionSpecified value
Voltage2±GroundConstantBattery voltage
Continuity1 GroundIgnition key setContinuityContinuity1±GroundIgnition key removedNo continuity
If circuit is not as specified, refer to BE±165 wiring diagram
and inspect the circuits connected to other parts.
(Key Unlock Warning Switch)
(See page BE±26)
Troubleshooting
You will find the cause of trouble more easily by properly using the table \
shown below. In this table, the numbers
indicate the order of priority of the cruses of trouble. Check each part in the \
order shown. If necessary, replace
the part.
See pageBE±4,21BE±165BE±26 ±±
TroubleParts
name
DOME FuseLiquid Crystal Inner MirrorKey Unlock Warning SwitchWire Harness
Liquid Crystal Inner Mirror does not operate.1234
BE±166±
BODY ELECTRICAL SYSTEM Liquid Crystal Inner Mirror System
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(Sliding Roof Control Relay)
REMOVAL AND INSTALLATION OF
SLIDING ROOF CONTROL RELAY
(See Sliding Roof on page BO±85)
INSPECTION OF SLIDING ROOF
CONTROL RELAY
INSPECT CONTROL RELAY CIRCUIT
Disconnect the connector from the relay and inspect the con-
nector on the wire harness side as shown in the chart.
Check forTest connectionConditionSpecified value
ContinuityA2 ± GroundSliding roof control OFF or UPNo continuityyg
switch position (TILT)DOWNContinuity
A6 ± GroundSliding roof control OFF or DOWNNo continuityg
switch position (TILT)UPContinuity
A7 ± GroundSliding roof control OFF or OPENNo continuityg
switch position (SLIDE)CLOSEContinuity
A8 ± GroundSliding roof control OFF or CLOSENo continuityg
switch position (SLIDE)OPENContinuity
B1 ± GroundConstantNo continuity
B1 ± B3ConstantContinuity
B2 ± GroundNo. 1 limit switch
p
osition
OFF (Sliding roof tilt up or
approx. 200 mm (7.87 in.)
opened)No continuity
positionON (Except for conditions
mentioned above)Continuity
B3 ± GroundConstantNo continuity
B4 ± GroundConstantContinuity
B5 ± GroundConstantContinuity
B6 ± GroundNo. 2 limit switch OFF (Sliding roof closed)No continuity
positionON (Sliding roof opened)Continuity
VoltageA1 ± GroundConstantBattery voltageg
A3 ± GroundIgnition switch positionLOCK or ACC ( * )No voltageg
ONBattery voltage
(*) Except within 60 seconds after turning the ignition key to the OFF\
position and both the driver's door and
the passenger's door are closed. If circuit is as specified, replace the relay.
BE±180
±
BODY ELECTRICAL SYSTEM Sliding Roof System
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Parts Inspection
(Fuel Lid Opener Switch)
REMOVAL AND INSTALLATION OF FUEL
LID OPENER SWITCH
REMOVE AND INSTALL FUEL LID OPENER SWITCH(a) Remove No. 1 lower finish panel.
(See Instrument Panel on page BO±113)
(b) Remove the key cylinder, then remove the fuel lid opener
switch assembly from the pad.
(c) Install the opener switch assembly and key cylinder to
the pad.
(d) Install the No. 1 lower finish panel. (See Instrument Panel on page BO±116)
INSPECTION OF FUEL LID OPENER
SWITCH
INSPECT SWITCH CONTINUITY
(a) Check that there is continuity between terminals with the
switch ON (Lever pulled).
(b) Check that there is no continuity between terminals with
the switch OFF (Lever free).
If continuity is not as specified, replace the switch assembly.
(Fuel Lid Opener Solenoid)
REMOVAL AND INSTALLATION OF FUEL
LID OPENER SOLENOID
REMOVE AND INSTALL FUEL LID SOLENOID (a) Disconnect the connector from the solenoid.
(b) Open the fuel lid and remove the solenoid lock nut, thenremove the solenoid.
(c) Install the solenoid in place with the lock nut.
(d) Connect the connector to the solenoid.
INSPECTION OF FUEL LID OPENER
SOLENOID
INSPECT SOLENOID OPERATION (a) Apply battery voltage to the terminals.
(b) Check that the solenoid operates in the open direction.
If operation is not as specified, replace the solenoid.
BE±192
±
BODY ELECTRICAL SYSTEM Fuel Lid Opener System
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CUSTOMER PROBLEM ANALYSIS CHECK SHEET
\
 
\

\
WIRELESS DOOR LOCK CONTROL System Check Sheet
Inspector 's
Name:
 


 


 

Registration No.
 


 Customer 's Name  Registration Year //
 


 


 

Frame No.
 


 


Date Vehicle
Brought In 

// 

Odometer Reading 


Km
Miles
 Date of Problem Occurrence\
 \
//
 

Frequency of Problem Occurrence
\
 
\

\

Constant  Sometimes ( times/per day, month)
 Once Only
 


Conditions at
 

Weather
\
 
\

\


Fine  Cloudy  Rainy  Snowy
 Various/Others
 


Conditions at
Time of Problem
Occurrence 

Outdoor Temperature
\
 
\

\


Hot  Warm  Cool
 Cold (Approx. 5F( 5C))
 


 

Place\
 
\

\

Everywhere  Specific Locality ( )
 

Date Transmitter Battery Last Replaced\
 
\

\
//
 \
 \

Whole wireless door lock control system does not operate
\

Whole wireless door lock control system does not operate.
 


\
 
\

\

Only door unlock operation is not possible.
 \
 \
Only door lock operation is not possible.
 


\
 
\

\

Only key confine prevention function is not possible.
 \
 \
 Wireless door lock function operates even when each door is opened.
 




\
 
\


\

\


Wireless door lock function incorrectly.
(Although one door is unlocked, when the transmitter
switch is pressed, all doors unlock.)
 





When RH door is unlocked.
 When LH door is unlocked.
 








\
 
\


\


\


\

\


Others
Problem Symptom
BE±444±
BODY ELECTRICAL SYSTEM Wireless Door Lock Control System
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PARTS REPLACEMENT
WIRELESS DOOR LOCK ECU REMOVAL
AND INSTALLATION
1. REMOVE WIRELESS DOOR LOCK ECU(a) Remove the rear seat.
(b) Remove the RH quarter trim panel.
(c) Disconnect the connectors.
(d) Remove the ECU.
2. INSTALL WIRELESS DOOR LOCK ECU For installation, follow the removal procedure in reverse.
WIRELESS DOOR LOCK ECU AND
TRANSMITTER REPLACEMENT
Disassembly and assembly of the wireless door lock ECU
and transmitter includes details of spare parts and replace-
ment procedure for defective parts found through trouble-
shooting.
Each part is a precision electronic component so handle with
care.
Destroy old ROM and transmitter to prevent reuse.
1. SPARE PARTS AND REPLACEMENT PROCEDURE FOR MALFUNCTIONING PARTS
(For malfunctioning transmitter)
(a) Prepare the new transmitter (with ROM).
(b) Remove the ECU from the vehicle.
(c) Remove the ROM from the ECU.
(d) Install the new ROM into the ECU.
(e) Install the ECU into the vehicle.
(f) Check that door lock remote control operation works.
(g) Cut the new key to the shape of the replaced key.
(For non±functioning battery)
(a) Prepare new battery (with O±ring).
(b) Remove battery and O±ring from transmitter.
(c) Install new battery and O±ring into transmitter.
±
BODY ELECTRICAL SYSTEM Wireless Door Lock Control SystemBE±449
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WIRING DIAGRAM
Door Key Lock and Unlock Switch Circuit (Unlock Side)
CIRCUIT DESCRIPTION
The door key lock and unlock switch is built into the door key cylinder. When the key is turned to the lock side,
the lock terminal of the switch is grounded, and when the key is turned to the unlock side the unlock terminal
is grounded.
Furthermore, the door key lock and unlock switch circuit has terminal +B\
connected inside the theft deterrent
and door lock ECU, when neither the lock or unlock terminal of the door key\
lock and unlock switch are grounded,
battery positive voltage is applied to the door key lock and unlock switch circuit of the wireless d\
oor lock ECU.
(Tr inside the ECU coming ON causes the wireless door lock ECU to output a \
signal to unlock all the doors.)
DIAGNOSTIC CHARTDIAGNOSTIC CHART
NGOK
Proceed to next circuit inspec-
tion shown on matrix chart (See
page
BE±454 ).
Check voltage between terminal UL1 of
ECU connector and ground.
Check and repair harness and connector
between ECU and key door key lock and
unlock switch.
1
BE±464±
BODY ELECTRICAL SYSTEM Wireless Door Lock Control System
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IGNITION SWITCH
Description
The ignition switch is supplied with power from the battery via a fusible l\
ink. Power is supplied to each fuse
and relay according to the position of the switch, whether ªCCº ``ONº or ªSTARTº. The key unlock warning
switch, which detects the set condition of the key, is built into this switch.
Parts Location
Wiring and Connector Diagrams
±
BODY ELECTRICAL SYSTEM Ignition SwitchBE±25
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