1991 LEXUS SC400 Service Repair Manual

brake rotor technical data spare tire winter tyres airbag off odometer

Load previous 8 pages

Page 65 of 4087

LEXUS SC400 1991 Service Repair Manual
DIAGNOSIS SYSTEM
Warning for A/C compressor lock
If compressor lock occurs during air conditioner operation, the
( A/C ) switch indicator on the air conditioner control assembly
starts blinking to w

Page 66 of 4087

LEXUS SC400 1991 Service Repair Manual
INDICATOR
1. Turn the ignition switch on while pressing the ari conditioner control
switch and REC swich
simultaneously.
2. Check that all the indicators light up and go off at 1 second interva

Page 67 of 4087

$LEXUS SC400 1991 Service Repair Manual DIAGNOSTIC CODE CHART If a malfunction code is displayed during the diagnostic code check (sens\ or check), check the circuit listed for that code in the table below (Proceed to the page given for th$

DIAGNOSTIC CODE CHART
If a malfunction code is displayed during the diagnostic code check (sens\
or check), check the circuit listed for
that code in the table below (Proceed to the page given for that circuit.)\
Code No.Diag. Code Detecting Condition
00 Normal
11 *1 Open or short in room temperature sensor circuit.
12 Open or short in ambient temperature sensor circuit.
13 Open or short in evaporator temperature sensor circuit.
14*2 Open or short in water temperature sensor circuit.
21*3 Open in solar sensor circuit.
21*3
Short in solar sensor circuit.
22*4
All conditions below are detected for 3 secs. or more.
(a) Engine rpm : 450 rpm or more.
(b) Ratio between engine and compressor rpm deviates 20% or more in c\
omparison to normal
operation.
23
Open in pressure sensor circuit.
Abnormal refrigerant pressure below 206 kPa (2.1 kgf/cm, 30 psi)
over 2,650 kPa (27 kgf/cm, 385 ps\
i)
31 Short to ground or power source circuit in Air Mix Damper position sens\
or circuit.
32 Short to ground or power source circuit in Air Inlet Damper position se\
nsor circuit.
33 Short to ground or power source circuit in Air Outlet Damper position s\
ensor circuit.
41 Air mix damper position sensor value does not change even if ECU operat\
es air mix servomotor.
42 Air inlet damper position sensor value does not change even if ECU oper\
ates air inlet servomotor.
43 Air outlet damper position sensor value does not change even if ECU ope\
rates air outlet
servomotor.
HINT: *1 If the room temp. is approx. ±20 °C (±4 °F) or lower, code 11 may be output even though the system
is normal.
*2 If the ambient temperature is approx. ±50 °C (±58 °F) or lower, a malfunction code may be output
even though the system is normal.
*3 If the check is being performed in a dark place, diagnostic code 21 (so\
lar sensor circuit abnormal) could be displayed.
In this case, perform diagnostic code check again while shining a light,\
such as an inspection light,
on the solar sensor.
If code 21 is still displayed, there could be trouble in the solar senso\
r circuit
AC±28
±
AIR CONDITIONING SYSTEM Troubleshooting
WhereEverybodyKnowsYourName

Page 68 of 4087

$LEXUS SC400 1991 Service Repair Manual Trouble AreaMemory*5See page ±±± Room temp. Sensor Harness or connector between room temp. sensor and A/C control assembly\$

Trouble AreaMemory*5See page
±±±
Room temp. Sensor
Harness or connector between room temp. sensor and A/C control assembly\
A/C control assemblyO
(8.5 min. or more)AC±44
Ambient temp. sensor
Harness or connector between ambient temp. sensor and A/C control assem\
bly
A/C control assemblyO
(8.5 min. or more)AC±46
Evaporator temp. sensor
Harness or connector between evaporator temp. sensor and A/C control
assembly A/C control assemblyO
(8.5 min. or more)AC±48
Water temp. sensor
Harness or connector between water temp. sensor and A/C control assembl\
y
A/C control assemblyO
(8.5 min. or more)AC±50
Solar sensor
H b d A/C l bl
±
AC 52 Solar sensor
Harness or connector between sensor and A/C control assembly
A/C control assemblyOAC±52
A/C control assemblyO
(8.5 min. or more)
Compressor drive belt Compressor lock sensor Compressor
Harness and connector between A/C control assembly and compressor,
compressor lock sensor
A/C control assembly
±AC±54
Pressure switch
Harness or connector between pressure switch and A/C control assembly
Refrigerant pipe line
A/C control assembly
±AC±56
Air mix damper position sensor A/C control assembly
Harness or connector between air mix damper position sensor and
A/C control assemblyO
(1 min. or more)AC±58
Air inlet damper position sensor A/C control assembly
Harness or connector between air inlet damper position sensor and
A/C control assemblyO
(1 min. or more)AC±62
Air outlet damper position sensor A/C control assembly
Harness or connector between air outlet damper position sensor and
A/C control assemblyO
(1 min. or more)AC±66
Air mix servomotor Air mix damper position sensor
Harness and connector between A/C control assembly and air mix position\
sensor
Harness and connector between A/C control assembly and air mix servomot\
or.O
(15 secs. or more)AC±58
AC±60
Air inlet servomotor Air inlet damper position sensor
Harness and connector between A/C control assembly and air inlet positi\
on sensor.
Harness and connector between A/C control assembly and air inlet servom\
otor.O
(15 secs. or more)AC±62
AC±64
Air outlet servomotor Air outlet damper position sensor
Harness and connector between A/C control assembly and air outlet posit\
ion
sensor.
Harness and connector between A/C control assembly and air outlet servo\
motor.
A/C control assembly
O
(15 secs. or more)AC±66
AC±68
±
AIR CONDITIONING SYSTEM TroubleshootingAC±29
WhereEverybodyKnowsYourName

Page 69 of 4087

LEXUS SC400 1991 Service Repair Manual
HINT:
wThe buzzer sounds when the display code changes.
w Codes are displayed in order from the smaller to the
larger numbers.
w To cancel the check mode, press the OFF switch.
AC±30±
AIR CONDITION

Page 70 of 4087

LEXUS SC400 1991 Service Repair Manual
A14±1
A14±2
A14±3
A14±4
A14±5
A14±6
A14±7
A14±8
A14±9
A14±10
A14±11
A14±12
A14±13
A14±14
A12±1
A14±15
A12±2
A12±3
A12±4
A12±5
A12±6
A12±7
A12±8
A12±9
A12±10A13±25
A13±24
A1

Page 71 of 4087

LEXUS SC400 1991 Service Repair Manual
STANDARD VALUE OF ECU TERMINAL
TerminalsSymbolsWiringColorConditionStandardValue
A14±1A14±7B ER W±BIG OFF10 ~ 14 V
A14±2 A14±3MH MCV R±YIG OFF13 ~ 19
A14±4A14±5MFRSMRECG G±RIG OF

Page 72 of 4087

LEXUS SC400 1991 Service Repair Manual
±
AIR CONDITIONING SYSTEM TroubleshootingAC±33
WhereEverybodyKnowsYourName

Load next 8 pages

Page: < prev 1-10 ... 33-40 41-48 49-56 57-64 65-72 73-80 81-88 89-96 97-104 ... 4088 next >

open hood fuel pump lock winter tyres tyre pressure check transmission fluid