1995 TOYOTA SUPRA warning light

DIAGNOSIS SYSTEM
The Electronically Controlled Transmission has built±in self±
diagnostic functions. If a malfunction occurs in the system,
the ECM stores the diagnostic trouble code in memory and
the O/D OFF (Overdrive OFF) indicator light blinks to inform
the driver. The diagnostic trouble code stored in memory can
be read out by the following procedure.
O/D OFF INDICATOR LIGHT INSPECTION
1. Turn the ignition switch ON.
2. Check if the O/D OFF indicator light lights up when the O/D
main switch is pushed out to OFF and goes off when the O/D
main switch is pushed in to ON.
HINT: If the O/D OFF indicator light does not light up or stay
on all the time, carry out the check for ºO/D OFF Indicator
Light Circuitº on page AT1±88.
DIAGNOSTIC TROUBLE CODE CHECK
1. Turn the ignition switch ON, but do not start the engine.
2. Push in the O/D main switch to ON.
HINT: Warning and diagnostic trouble codes can be read only
when the O/D main switch is ON. If it is OFF, the O/D OFF indi-
cator light up will light continuously and will not blink.
3. Using SST, connect terminals TE1 and E1 of the DLC 1 or
DLC2.
SST 09843±18020
4. Read the diagnostic trouble code indicated by the number of
times the O/D OFF indicator light blinks.
HINT: If the system is operating normally, the light will blink
2 times per second. AT1±34
± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

*1 ªº mark means ºO/D OFFº indicator light blinks once every 2 seconds.
ºXº mark means ºO/D OFFº indicator light never blinks.
*
2ªº marks means the ECM memorizes the malfunction code if the ECM detects the diagnostic trouble code
detection condition.
*
3 This indicates items for which º2 trip detection logicº is used. With this logic, when a logic malfunction is
first detected, the malfunction is temporarily stored in the ECM memory. If the same case is detected again
during the second drive test, this second detection causes the O/D OFF Indicator Light to blink. The 2 trip
repeats the same mode twice. (However, the IG switch must be turned OFF between the 1st trip and 2nd
trip.)
HINT:
wIf the malfunction returns to normal while a malfunction warning is being output, the O/D OFF indicator
light stops blinking and goes off.
However, the diagnostic trouble code is retained in memory until it is cleared from memory.
wIf the diagnosis system outputs a diagnostic trouble code even though the O/D OFF indicator was not
blinking, there is intermittent trouble. Check all the connections in the circuits corresponding to that
code.
wIf the vehicle speed sensors No.1 and No.2 happen to fail simultaneously, the ECM will neither alert
the driver by blinking the O/D OFF indicator nor record any diagnostic trouble code. It will, however,
decide that the vehicle can be driven only in 1st and none of the other gears, so shifting upward will
then be prohibited.
wCodes 46, 62, 63 and 64 are limited to short or open circuits in the electrical system comprised of the
solenoids, wire harnesses, and connectors. The ECM is unable to detect mechanical trouble (sticking,
for example) in the solenoid valves. AT1±54
± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

DIAGNOSIS SYSTEM
The automatic transmission has built±in self±diagnostic
functions. If a malfunction occurs in the system, the ECM
stores the diagnostic trouble code in memory and the O/D
OFF (Overdrive OFF) indicator light blinks to inform the driv-
er. The diagnostic trouble code stored in memory can be read
out by the following procedure.
O/D OFF INDICATOR LIGHT INSPECTION
1. Turn the ignition switch ON.
2. Check if the O/D OFF indicator light lights up when the O/D
main switch is pushed out to OFF and goes off when the O/D
main switch is pushed in to ON.
HINT: If the O/D OFF indicator light does not light up or stay
on all the time, carry out the check for ºO/D OFF Indicator
Light Circuitº on page AT2±108.
DIAGNOSTIC TROUBLE CODE CHECK
1. Turn the ignition switch ON, but do not start the engine.
2. Push in the O/D main switch to ON.
HINT: Warning and diagnostic trouble codes can be read only
when the O/D main switch is ON. If it is OFF, the O/D OFF indi-
cator light up will light continuously and will not blink.
3. Using SST, connect terminals TE1 and E1 of the DLC 1 or
DLC2.
SST 09843±18020
4. Read the diagnostic trouble code indicated by the number of
times the O/D OFF indicator light blinks
(See next page).
HINT: If the system is operating normally, the light will blink
2 times per second. AT2±34
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

*1: ºOº mark means ºO/D OFFº light blinks once every 2 seconds.
ºXº mark means ºO/D OFFº light never blinks.
*2: ºOº marks means the ECM memorizes the malfunction code if the ECM detects the diagnostic trouble code
detection condition.
*3: This indicates items for which º2 trip detection logicº is used. With this logic, when a logic malfunction is
first detected, the malfunction is temporarily stored in the ECM memory. If the same case is detected again
during the second drive test, this second detection causes the O/D OFF indicator light to blink. The 2 trip
repeats the same mode twice. (However, the IG switch must be turned OFF between the 1st trip and 2nd
trip.)
HINT:
wIf the malfunction returns to normal while a malfunction warning is being output, the O/D OFF indicator
light stops blinking and goes off.
However, the diagnostic trouble code is retained in memory until it is cleared from memory.
wIf the diagnosis system outputs a diagnostic trouble code even though the O/D OFF indicator was not
blinking, there is intermittent trouble. Check all the connections in the circuits corresponding to that
code.
wCodes 42, 62, 63 and 64 are limited to short or open circuits in the electrical system comprised of the
solenoids, wire harnesses, and connectors. The ECM is unable to detect mechanical trouble (sticking,
for example) in the solenoid valves.
wIf the speed sensors No.1 and No.2 happen to fail simultaneously, the ECM will neither alert the driver
by blinking the O/D OFF indicator nor record any diagnostic trouble code. It will, however, decide that
the vehicle can be driven only in 1st and none of the other gears, shifting upward will then be
prohibited. AT2±58
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

PREPARATION
SST (SPECIAL SERVICE TOOLS)
09843±18020Diagnosis Check Wire
09808±14010Fuel Sender Gauge Tool Assy
09950±50010Puller C Set
RECOMMENDED TOOLS
09082±00050TOYOTA Electrical Tester Set


EQUIPMENT
 
 Voltmeter
 
 
 Ammeter 
 Ohmmeter 
 Test lead 
 Thermometer Engine oil level warning switch, Seat heater
 Syphon Brake fluid level warning switch
 Oil bath Engine oil level warning switch
 Bulb (3.4 W) Fuel sender gauge, Seat belt warning relay Bulb (21 W) Turn signal flasher relay Dry cell battery Fuel sender gauge 
 Heat light
 
 Seat heater
 Torque wrench 
 Masking tape Rear window defogger wire
 Tin foil Rear window defogger wire
SSM (SPECIAL SERVICE MATERIAL)
 

DuPont Paste No. 4817 or
equivalent
 

Rear window defogger
 
 
equivalent 
 
± BODY ELECTRICAL SYSTEMPREPARATIONBE±3

TROUBLESHOOTING
The table below will be useful for you in troubleshooting these electrical problems. The most likely causes
of the malfunction are shown in the order of their probability. Inspect each part in the order shown, and
replace the part when it is found to be faulty.
 Trouble Parts name (See page)
 
 
 
ºHazardº and ºTurnº do not light up
 
 
 
1. Hazard Warning Switch (BE±22)
2. Turn Signal Flasher (BE±22)
3. Wire Harness
 
 
 
The flashing frequency is abnormal
 
 
 
1. Bulb
2. Turn Signal Flasher (BE±22)
3. Wire Harness
 Hazard warning light does not light up
(Turn is normal) 1. HAZ±HORN Fuse (BE±5)
2. Wire Harness
 
 Hazard warning light does not light up in one direction
 
 1. Hazard Warning Switch (BE±22)
2. Wire Harness
 
 
 
 
*1 Turn signal does not light up
 
 
 
 
1. Ignition Switch (BE±8)
2. TURN Fuse (BE±6)
3. Turn Signal Switch (BE±21)
4. Wire Harness
 
 
 
*2 Turn signal does not light up
 
 
 
1. TURN Fuse (BE±6)
2. Turn Signal Switch (BE±21)
3. Wire Harness
 
 Turn signal does not light up in one direction
 
 
1. Turn Signal Switch (BE±21)
2. Wire Harness
 
 Only one bulb does not light up
 
 
1. Bulb
2. Wire Harness
*1: Combination Meter, Wiper and Washer do not operate.
*
2: Combination Meter, Wiper and Washer are normal.
TURN SIGNAL SWITCH INSPECTION
INSPECT SWITCH CONTINUITY 
 Switch position
 
 Tester connection to
terminal number
 
 Specified condition
 
 Left turn
 
 A1 ± A5
 
 Continuity 
 Neutral
 
 ±
 
 No continuity
 Right turn A1 ± A8 Continuity
If continuity is not as specified, replace the switch.
± BODY ELECTRICAL SYSTEMTURN SIGNAL AND HAZARD WARNING SYSTEMBE±21

HAZARD WARNING SWITCH
INSPECTION
INSPECT SWITCH CONTINUITY
 
 Condition
 
 Tester connection to
terminal number
 
 Specified condition
 Switch OFF 7±10 Continuity 
 Switch ON
 
 7±8
4±5±6±9
 
 Continuity
 
 Illumination circuit
 
 2±3
 
 Continuity
If continuity is not as specified, replace the switch.
TURN SIGNAL FLASHER INSPECTION
INSPECT FLASHER OPERATION
(a) Connect the terminal 2 to battery positive (+) terminal and the
terminal 3 to battery negative (±) terminal.
(b) Connect the 2 turn signal light bulbs parallel to each other to
terminals 1 and 3, check that the bulbs flash.
HINT: The turn signal lights should flash between 60 and 120
times per minute. BE±22
± BODY ELECTRICAL SYSTEMTURN SIGNAL AND HAZARD WARNING SYSTEM

WARNING LIGHTS
 Trouble Parts name (See page)
 
 
 
 
 
Warning lights do not light up
(Except Discharge and Door Open)
 
 
 
 
 
1. Bulb
2. IGN Fuse (BE±6)
3. Ignition Switch (BE±8)
4. Meter Circuit Plate (BE±44)
5. Wire Harness
6. Generator
 
 
 
 
 
 
Brake Warning Light does not light up
 
 
 
 
 
 
1. Bulb
2. Brake Fluid Level Warning Switch (BE±52)
3. Parking Brake Switch (BE±52)
4. Bulb Check Relay
5. Meter Circuit Plate (BE±44)
6. Wire Harness
 
 
 
 
 
Seat Belt Warning Light does not light up
 
 
 
 
 
1. Bulb
2. Seat Belt Buckle Switch (BE±56)
3. Integration Relay (BE±55)
4. Meter Circuit Plate (BE±44)
5. Wire Harness
 
 
 
 
Engine Oil Level Warning Light does not light up
 
 
 
 
1. Bulb
2. Engine Oil Level Switch (BE±51)
3. Meter Circuit Plate (BE±44)
4. Wire Harness
 
 
 
Low Oil Pressure Warning Light does not light up
 
 
 
1. Bulb
2. Low Oil Pressure Warning Switch (BE±51)
3. Meter Circuit Plate (BE±44)
4. Wire Harness
 
 
 
 
 
 
 
Door Open Warning Light does not light up
 
 
 
 
 
 
 
1. Bulb
2. DOME Fuse (BE±5)
3. Door Courtesy Switch (BE±54)
4. Luggage Room Light Switch (BE±28)
5. Integration Relay
6. Meter Circuit Plate (BE±44)
7. Wire Harness
 
 
 
 
Master Warning Light does not light up
 
 
 
 
1. Bulb
2. Telltale Light (BE±48)
3. Meter Circuit Plate (BE±44)
4. Wire Harness
BE±42± BODY ELECTRICAL SYSTEMCOMBINATION METER