LEXUS SC400 1991 Service Repair Manual

ELECTRONIC CONTROL COMPONENTS
INSPECTION
AT0GM±02
1. INSPECT SHIFT LOCK CONTROL ECMUsing a voltmeter, measure the voltage at each terminal.
 Connector Terminal\
 \
Measuring condition Voltage (V)  ACC±E\
 \
IG SW ACC position 10±14 


 

IG±E\
 
\

\
IG SW ON position 

10±14
 A STP±E\
 \
Depress brake pedal 10±14
 
A
 \
 \


IG SW ACC position and P position 0
  KLS±E\
 \
 R, N, D, 2, L, position 7.5±11
  \
 \
 R, N, D, 2, L position (after one second) 6±9.5
  \
 \

IG SW ON position and P position 0
 
B
 
SLS
± SLS 
\
 \
 Depress brake pedal 8±13.5 B SLS
± SLS \
 \
 Depress brake pedal (after 20 seconds) 6±8.5 


 


\
 
\

\

R, N, D, 2, L position 

0
  P1P\
 \


IG SW ON, P position and depress brake pedal 0
 C 
P1±P
\
 \
 R, N, D, 2, L position 9±13.5
 C P2±P\
 \

IG SW ACC position and P position 9±13.5
  P2±P\
 \
 R, N, D, 2, L position 0
2. INSPECT SHIFT LOCK 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 n
terminals.
Standard resistance:
20±28

If resistance value is not as specified, replace the solenoid.
(c) Apply the battery positive voltage between terminals. At this time, confirm that the solenoid operates.
If solenoid operation is not as specified, replace solenoid.
AT±28
±
A304E (1UZ±FE) AUTOMATIC TRANSMISSION SHIFT LOCK SYSTEM
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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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±Memo±
AT00X±01
AT±30±
A304E (1UZ±FE) AUTOMATIC TRANSMISSION SHIFT LOCK SYSTEM
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TROUBLESHOOTING
±
A304E (1UZ±FE) AUTOMATIC TRANSMISSION TROUBLESHOOTINGAT±31
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HOW TO PROCEED WITH TROUBLESHOOTING
AT09N±0D
1. CUSTOMER PROBLEM ANALYSISUsing the customer problem analysis check sheet for reference, ask the c\
ustomer in as much detail as
possible about the problem.
2. CHECK AND CLEAR THE DIAGNOSTIC TROUBLE CODES (PRECHECK) Before confirming the problem symptom, first check if there are any diagnostic\
trouble malfunction codes
stored in memory. When there are malfunction codes, make a note of them, then clear them\
and proceed
to ª3. Problem Symptom Confirmationº.
3. PROBLEM SYMPTOM CONFIRMATION Confirm the problem symptoms.
4. SYMPTOM SIMULATION If the problem does not reappear, be sure to simulate the problem by mainly checking the circuits indica\
ted
by the diagnostic trouble code in step 2., using ªProblem Simulation me\
thodº.
5. DIAGNOSTIC TROUBLE CODE CHECK Check the diagnostic trouble codes. Check if there is abnormality in the\
sensors or the wire harness.
If a malfunction code is output, proceed to ª6. Diagnostic Trouble Code Chartº.
If the normal code is output, proceed to ª11. Matrix Chart of Problem Symptomsº.
Be sure to proceed to ª6. Diagnostic Trouble Code Chartº after the steps 2. and 3. are completed.
If troubleshooting is attempted only by following the malfunction code sto\
red in the memory is output, errors
could be made in the diagnosis.
6. DIAGNOSTIC TROUBLE CODE CHART If a malfunction code is confirmed in the diagnostic trouble code check, p\
roceed to the inspection proce-
dure indicated by the matrix chart for each diagnostic trouble code.
7. PRELIMINARY CHECK Carry out a preliminary check of the transmission oil level, throttle ca\
ble adjustment, etc.
8. SHIFT POSITION SIGNAL CHECK
Carry out the shift position signal check when the transmission gears do\
not up±shift, down±shift or lock±
up. This is to check the output condition from the ECM to each solenoid. If the r\
esults are NG, then it is
likely that the trouble is in the electrical system (particularly in th\
e sensors or the ECM).
Proceed to Part 1 (Electrical System) under ª11. Matrix Chart of Problem Symptomsº. If all the circuits speci-
fied in Part 1 are OK, check the ECM and replace it.
9. MECHANICAL SYSTEM TEST (Stall Test, Time Lag Test, Line Pressure Test, Accumulator Back Pressure Test)
If the malfunction is found in the stall test, time lag test, line press\
ure test or accumulator back pressure
test, check the parts indicated in the respective tests. If the problem is th\
at ªshift shock is largeº, perform
the accumulator back pressure test.
10. MANUAL SHIFTING TEST If the results of the manual driving test are NG, it is likely that the trouble is in the mechanical system or
hydraulic system. Proceed to Part 2 (Mechanical System) under the Matrix Chart \
of Problem Symptoms.
AT±32
±
A304E (1UZ±FE) AUTOMATIC TRANSMISSION TROUBLESHOOTING
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11. MATRIX CHART OF PROBLEM SYMPTOMSIf the normal code is confirmed in the diagnostic trouble code check, perform inspection according to the
inspection order in the matrix chart of problem symptoms. Perform diagno\
sis of each circuit or part in the
order shown in the Matrix Chart. The Matrix Chart contains 3 chapters, Electronically Controlled Circuits
in Chapter 1, On±vehicle Inspection in Chapter 2 and Off±vehicle Inspection in Chapter 3. If all the circuits
indicated in Chapter 1 are normal, proceed to Chapter 2. If all the parts indicated i\
n Chapter 2 are normal,
proceed to Chapter 3. If all the circuits and parts in Chapter 1±Chapter 3 are normal and the trouble still
occurs, check and replace the ECM.
12. CIRCUIT INSPECTION Perform diagnosis of each circuit in accordance with the inspection order confirmed in 6. and 11. Judge
whether the cause of the problem is in the sensor, actuators, wire harness and connectors, or the ECM.
In some cases, the Flow Chart instructs that a throttle signal check, brak\
e signal check or kick down signal
check (in test mode) be performed. These are diagnosis functions used \
to check if signals are being input
correctly to the ECM.
13. PARTS INSPECTION Check the individual parts of the mechanical system and hydraulic system in t\
he order of the numbers indi-
cated in the Matrix Chart.
14. REPAIRS After the cause of the problem is located, perform repairs by following the i\
nspection and replacement pro-
cedures in this manual or '94 A340E and A341E Automatic Transmission Repair Manual (for LEXUS
SC400).
15. CONFIRMATION TEST
After completing repairs, confirm not only that the malfunction is eliminated\
, but also conduct a test drive,
etc., to make sure the entire electronically controlled transmission system i\
s operating correctly.
±
A304E (1UZ±FE) AUTOMATIC TRANSMISSION TROUBLESHOOTINGAT±33
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P. AT±35P. AT±37 ~ AT±38
P. AT±47
P. AT±60 P. AT±39
P. AT±50
P. AT±59
P. AT±65
P. AT±66 P. AT±68
P. AT±70
P. AT±78 ± AT±120
P. AT±37 ~ AT±38
P. IN±26
P. AT±41
AT±34
±
A304E (1UZ±FE) AUTOMATIC TRANSMISSION TROUBLESHOOTING
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MIRROR
Outside Rear View Mirror
COMPONENTS
REMOVAL AND INSTALLATION OF
OUTSIDE REAR VIEW MIRROR
HINT: Install the mirror by following the removal sequence
in reverse.
1. DISCONNECT BATTERY CABLE FROM NEGATIVE TERMINAL
CAUTION: Work must be started after approx. 20 se-
conds or longer from the time the ignition switch is
turned to the ºLOCKº position and the negative (±) termi-
nal cable is disconnected from the battery.
2. REMOVE DOOR TRIM UPPER PANEL Removal: (See step 5 on page BO±34)
Installation: (See step 16 on page BO±40)
3. REMOVE MIRROR (a) Connect the connector, install the mirror with two bolts.
(b) Connect the connector, install the speaker with twobolts.
BO±42
±
BODY Mirror (Outside Rear View Mirror)
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REPLACEMENT OF OUTSIDE REAR
VIEW MIRROR
1. IF NECESSARY, DISCONNECT MIRROR(a) Insert the shop rag between the mirror and the mirrorbody to wrap up the mirror in the shop rag.
(b) Pull up the lower side of the shop rag to disconnect the mirror joint.
(c) Pull up the mirror and disconnect it.
2. CONNECT MIRROR (a) Connect the claws (A) and set the mirror to the mirrorbody.
(b) Push the mirror to connect the claws (B) and connect it.
±
BODY Mirror (Outside Rear View Mirror)BO±43
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Inner Rear View Mirror
COMPONENTS
REMOVAL AND INSTALLATION OF
INNER REAR VIEW MIRROR
HINT: Install the mirror following removal sequence in re-
verse.
1. REMOVE CENTER VISOR (See step 4 on page BO±123)
2. REMOVE INNER REAR VIEW MIRROR (a) Remove the mirror from the mirror base.
(b) Disconnect the connector.
BO±44
±
BODY Mirror (Inner Rear View Mirror)
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