Page 814 of 1807

F03385BE6653F03386F03387
ON
IDL1
- DIAGNOSTICSABS & TRACTION CONTROL SYSTEM
DI-523
751 Author: Date:
1997 SUPRA (RM502U)
INSPECTION PROCEDURE
HINT:
The main throttle position sensor signal is transmitted to the throttle control ECU from ECM, so if an error
occurs at the engine side, the throttle control ECU also detects it.
If DTC No. P0120 or P0121 is being output for the engine, troubleshoot the engine first.
1 Is DTC output for the engine?
Check DTC on page DI-147.
YES Repair circuit indicated by the code output.
NO
2 Check voltage between terminal IDL1 of throttle control ECU and body ground.
PREPARATION:
(a) Remove throttle control ECU with connectors still con-
nected.
(b) Disconnect the vacuum hose from the throttle opener,
and apply vacuum to the throttle opener.
(c) Turn ignition switch ON.
CHECK:
Measure voltage between terminal IDL1 of throttle control ECU
and body ground, when the throttle valve is fully closed and fully
open.
OK:
Throttle valve positionVoltage
Fully closed0 - 3 V
Fully open9 - 14 V
OK Go to step 4.
NG
Page 818 of 1807

F03378BE6653F03379F03380
ON
IDL2
- DIAGNOSTICSABS & TRACTION CONTROL SYSTEM
DI-527
755 Author: Date:
1997 SUPRA (RM502U)
INSPECTION PROCEDURE
HINT:
The sub-throttle position sensor signal is transmitted to the throttle control ECU from ECM, so if an error
occurs at the engine side, the throttle control ECU also detects it.
If DTC No. P1400 or P1401 is being output for the engine, troubleshoot the engine first.
1 Is DTC output for the engine?
Check DTC on page DI-147.
YES Repair circuit indicated by the code output.
NO
2 Check voltage between terminal IDL2 of throttle control ECU and body ground.
PREPARATION:
(a) Remove throttle control ECU with connectors still con-
nected.
(b) Remove intake air duct.
(c) Disconnect sub-throttle valve motor connector.
(d) Turn ignition switch ON.
CHECK:
Measure voltage between terminal IDL2 of throttle control ECU
and body ground, when the sub-throttle valve is fully closed
and fully open.
OK:
Sub-throttle valve positionVoltage
Fully closed0 - 3 V
Fully open9 - 14 V
OK Go to step 4.
NG
3 Check for open and short in harness and connector between terminal IDL2 of
throttle control ECU and sub-throttle position sensor (See page IN-28).
NG Repair or replace harness or connector.
OK
Page 822 of 1807
BE6653F03391F03392
ON
NE
(Reference)
3 - 6 V
Below 1V
3 ms. 3 ms.
- DIAGNOSTICSABS & TRACTION CONTROL SYSTEM
DI-531
759 Author: Date:
1997 SUPRA (RM502U)
INSPECTION PROCEDURE
HINT:
If DTC No. P0335 is being output for the engine, troubleshoot the engine first.
1 Check for open and short in harness and connector between terminal NE of
throttle control ECU and terminal NEO of ECM (See page IN-28).
NG Repair or replace harness or connector.
OK
2 Check voltage between terminal NE of throttle control ECU and body ground.
PREPARATION:
(a) Remove throttle control ECU with connectors still con-
nected.
(b) Turn ignition switch ON.
CHECK:
Measure voltage between terminal NE of throttle control ECU
and body ground for the engine conditions below.
OK:
Engine conditionVoltage
OFF (IG ON)3 - 6 V or below 1 V
ON (Idling)2 - 3 V (Pulse)
NG Check and replace ECM.
OK
Check and replace throttle control ECU.
Page 823 of 1807
F03393
Trottle Conrol ECU
5V
5V EFIF
EFI+
EFI-
GE11 P
B
W
(Shielded) ECM
EFIF
EFI+
EFI-
T15
T1517
7
20
15
T15 67
E9
27
E10
26
E10 T15
DI-532
- DIAGNOSTICSABS & TRACTION CONTROL SYSTEM
760 Author: Date:
1997 SUPRA (RM502U)
DTC 42 Engine Control System Malfunction
CIRCUIT DESCRIPTION
If trouble in the engine control system causes the malfunction indicator light to light up, this information is
transmitted from the ECM to the throttle control ECU. Then throttle control ECU may prohibit TRAC control
as a result.
DTC No.DTC Detecting ConditionTrouble Area
42ECM detected malfunction signal ON (output voltage at termi-
nal EFIF is 4.5 V or more, or 5.5 V or less for 1 sec. or more).Wire harness and connector (EFIF circuit)
ECM
Throttle control ECU
WIRING DIAGRAM
INSPECTION PROCEDURE
1 Check the DTC for the engine (See page DI-147).
*1 Repair engine control system according to the
code output.
*2
*1: Output NG code
*2: Malfunction indicator light remains ON
DI4W3-01
Page 826 of 1807
F03368
Throttle Control
ECU R/B No.5
Throttle Control Relay
(TRAC Solenoid Relay)
R/B
No.2
Battery+B
RLY-
RLY+
E01 9
12
4
13
BR L-B BR-BL-R 14
11
12
L-B L-Y
TRAC
L-R
BR-B
B
2
12A2
15
4 3
51
65
5
T15
EC IB5 T16T16T16
IB5 IB5
- DIAGNOSTICSABS & TRACTION CONTROL SYSTEM
DI-535
763 Author: Date:
1997 SUPRA (RM502U)
DTC 51, 52 Power Source Circuit
CIRCUIT DESCRIPTION
DTC No.DTC Detecting ConditionTrouble Area
51In case power source voltage comes down, sub-throttle valve
angle difference occurs.Wire harness and connector (+B and E01 circuit)
Throttle control ECU
52Engine speed is 500 rpm or more and throttle relay is ON and
ECU terminal +B voltage is less than 8 V for 10 sec. or more.
Battery
IC regulator
Wire harness and connector (+B and E01 circuit)
Throttle control ECU
WIRING DIAGRAM
INSPECTION PROCEDURE
1 Check battery positive voltage.
OK:
Voltage: 10 - 14 V
NG Check and repair the charging system.
OK
DI4W5-01
Page 836 of 1807
F03400
J/B No.1
GAUGE 12
Throttle Control
ECU
WA ABS
Warning Light
Y L
L
L
L ABS ECU
12V
WA5 11
A20
IF2T5
T161E 42
T5
12
- DIAGNOSTICSABS & TRACTION CONTROL SYSTEM
DI-545
773 Author: Date:
1997 SUPRA (RM502U)
DTC 81 ABS Control System Malfunction
CIRCUIT DESCRIPTION
DTC No.DTC Detecting ConditionTrouble Area
81Engine speed is 500 rpm or more and ABS warning light is ON
for 12 sec. or more.Wire harness and connector (WA circuit)
ABS ECU
Throttle control ECU
WIRING DIAGRAM
INSPECTION PROCEDURE
1 Check the DTC for the ABS (See page DI-501).
*1 Repair ABS control system according to the
code output.
*2
*1: Output NG code
*2: Malfunction indicator light remains ON
DI4W8-01
Page 900 of 1807

DI4WW-01
THEFT DETERRENT SYSTEM Check Sheet
Inspector 's name:
Customer 's Name
Date of VehicleRegistration No.
Registration Year
Frame No.
Odometer Reading / /km
Mile
Weather Conditions
When Problem
Occurred Frequency Problem OccursWeather
Outdoor temperature
/ /
Constant Sometimes ( Times per day, month)
Once only Brought in
Theft deterrent system cannot be set.
Indicator light does not flash when the theft deterrent system is set.
(It stays on or does not light at all.)
Theft deterrent system
does not operate. When unlocked using the
door lock knob.
When the engine hood is
opened.
System cannot be
canceled once set. When door is unlocked using key or wireless door lock control system.
When the key is inserted in the ignition key cylinder and turned to ACC or ON
position.
(However, only when the system has never operated)
When the luggage compartment door is opened with the key.
System cannot be
canceled during warning
operation. When door is unlocked using key or wireless door lock control system.
When the key is inserted in the ignition key cylinder and turned to ACC or ON
position.
Warning operation starts when the system is set and the door or luggage compartment door is opened with
the key.
Others.
Date Problem First Occurred
Fine Cloudy Rainy Snowy
Various/Others
Hot Warm Cool
Cold (Approx. 5F ( 5C))
Problem Symptom
Malfunction
Horns only
Theft deterrent horn only
Headlights only
Taillights only
Starter cut only
Door lock operation only
- DIAGNOSTICSTHEFT DETERRENT SYSTEM
DI-609
837 Author: Date:
1997 SUPRA (RM502U)
CUSTOMER PROBLEM ANALYSIS CHECK
Page 901 of 1807

DI4WX-01
DI-610
- DIAGNOSTICSTHEFT DETERRENT SYSTEM
838 Author: Date:
1997 SUPRA (RM502U)
PRE-CHECK
1. Setting Conditions:
SETTING OF THE THEFT DETERRENT SYSTEM
(a) Close all the doors.
(b) Close the engine hood and luggage compartment door.
(c) Remove the ignition key from the ignition key cylinder.
2. Setting Operation:
SETTING OF THE THEFT DETERRENT SYSTEM
When any of the following operations (a) or (c) is done, the theft deterrent indicator light will light up as de-
scribed.
(1) Lock the left or right front door using the key. (All doors are locked by key-interlinked lock opera-
tion)
(2) With the rear doors locked and with one of the front doors locked, lock the other front door without
using the key (keyless door lock).
Elapsed time after operationIndicator light
Within about 30 secondsLight up
After about 30 secondsBlinks *1
*1: 1 sec. on, 1 sec. off
HINT:
When the theft deterrent system is set, doors cannot be locked or unlocked with the door lock control switch
and the luggage compartment door cannot be unlocked with the luggage compartment door opener switch.
3. Cancelling Operation:
CANCELING OF THE THEFT DETERRENT SYSTEM IN THE SET CONDITION
HINT:
Check if the theft deterrent indicator light is blinking.
When any of the following operation (a), (b), (c) or (d) is done, the theft deterrent system is canceled
and indicator light will go off.
(a) Unlock the left or right front door using the key.
(b) Insert the ignition key in the ignition key cylinder and turn it to the ACC or ON position. (This is operative
only when the theft deterrent system has never operated.)
(c) Unlock the luggage compartment door with the key. *
1
*1: The theft deterrent systems is temporarily canceled only while the luggage compartment door is open.
Approximately 2 seconds after the luggage compartment door is closed, the theft deterrent system is reset.