Page 817 of 1807

F03376
ECM
VTO2
IDL2
Sub-throttle
Position Sensor 39
E10
E963
GR-R G-O
T1519
GR-R GR-R 3
T15
26
T15BR 12V
VTA2
12V
12V
GE01
E01 B BA A
12V
12V 12
T15
T15
25
T15
T15
23
T15
13
T15 W-B (Shielded)
L
Y
R
B Sub- throttle
Valve Motor
6
4
3
1
2
ED EC
IDL2
E1 11
24
Throttle Control ECU DI-526
- DIAGNOSTICSABS & TRACTION CONTROL SYSTEM
754 Author: Date:
1997 SUPRA (RM502U)
DTC 32 Sub-Throttle Position Sensor Circuit
CIRCUIT DESCRIPTION
This sensor detects the opening angle of the sub-throttle valve and sends the appropriate signals to the
ECU. If a trouble signal is input, the ECU prohibits TRAC control.
DTC No.DTC Detecting ConditionTrouble Area
32
Conditions (1) and (2) continue for 0.5 sec. or more:
(1) Sub-throttle position sensor circuit is open and E1 or +B
circuit is short.
(2) Instead of sub-throttle valve motor is driven fully close,
IDL2 of sub-throttle position sensor will not come ON.Sub-throttle position senor
Sub-throttle valve motor
Sub-throttle valve
Wire harness and connector (sub-throttle position sensor
and E1 circuit)
Throttle control ECU
WIRING DIAGRAM
DI4W1-01
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 819 of 1807

F03378BE6653F03382F03383
ON
VTA2 (-)(+)
DI-528
- DIAGNOSTICSABS & TRACTION CONTROL SYSTEM
756 Author: Date:
1997 SUPRA (RM502U)
4 Check voltage between terminal VTA2 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 VTA2 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 - 0.8 V
Fully open3.2 - 4.9 V
OK Go to step 6.
NG
5 Check for open and short in harness and connector between terminals VTA2 of
throttle control ECU and VTO2 of ECM (See page IN-28).
NG Repair or replace harness or connector.
OK
Check and replace throttle control ECU.
6 Check sub-throttle position sensor (See page DI-243).
NG Adjust or replace sub-throttle position sensor
(See page SF-44).
OK
Page 820 of 1807
F03377
63
1
4
- DIAGNOSTICSABS & TRACTION CONTROL SYSTEM
DI-529
757 Author: Date:
1997 SUPRA (RM502U)
7 Check sub-throttle valve motor.
PREPARATION:
Disconnect sub-throttle valve motor connector.
CHECK:
Check continuity between each terminal of sub-throttle valve
motor connector.
OK:
Terminals 1 and 3Continuity
Terminls 4 and 6
Continuity
(Reference value 0.40 - 0.48 W)
NG Replace sub-throttle valve motor.
OK
8 Check for open and short in harness and connector between terminal E1 of
throttle control ECU and body ground (See page IN-28).
NG Repair or replace harness or connector.
OK
Check and replace throttle control ECU.
Page 821 of 1807
BR5440
Throttle Control ECU
5V
NE
T1516
P-L 38
E10 NEO ECM DI-530
- DIAGNOSTICSABS & TRACTION CONTROL SYSTEM
758 Author: Date:
1997 SUPRA (RM502U)
DTC 41 NE Signal Circuit
CIRCUIT DESCRIPTION
The throttle control ECU receives engine speed signals (NE signals) from the ECM.
DTC No.DTC Detecting ConditionTrouble Area
41While engine is running, throttle control ECU detected 0 rpm
signal for 0.8 sec. or more.Wire harness and connector (NE circuit)
ECM
Throttle control ECU
WIRING DIAGRAM
DI4W2-01
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 824 of 1807
- DIAGNOSTICSABS & TRACTION CONTROL SYSTEM
DI-533
761 Author: Date:
1997 SUPRA (RM502U)
2 Check for open and short in harness and connector between terminal EFIF of
throttle control ECU and terminal EFIF of ECM (See page IN-28).
NG Repair or replace harness or connector.
OK
Check and replace throttle control ECU.