TOYOTA SUPRA 1997 Service Repair Manual

Input SignalIndicator Light
Blinking Pattern
Drive at about
40 km/h (25 mph)
or below
Drive at about
40 km/h (25 mph)
or higherLightON
OFF
LightON
OFF
DI-680
- DIAGNOSTICSCRUISE CONTROL SYSTEM
908 Author
: Date
:
1997 SUPRA (RM502U)
INSPECTION PROCEDURE
1 Input signal check.
CHECK:
(a) See input signal check on page
(b) Check indicator light operation when driving with vehicle
speed above 40 km/h (25 mph), and with vehicle speed
below 40 km/h (25 mph).
OK:
Vehicle speed above 40 km/h (25 mph):
Indicator light blinks
Vehicle speed below 40 km/h (25 mph):
Indicator light stays on
OK Check and replace cruise control ECU
(See page IN-28).
NG
2 Check harness and connector between speed meter and cruise control ECU
(See page IN-28).
NG Repair or replace harness or connector.
OK
3 Check vehicle speed sensor (See page BE-43).
NG Replace vehicle speed sensor.
OK
Check and replace cruise control ECU
(See page IN-28).

- DIAGNOSTICSCRUISE CONTROL SYSTEM
DI-681
909 Author
: Date
:
1997 SUPRA (RM502U)
DTC 23 Vehicle Speed Signal Abnormal
CIRCUIT DESCRIPTION
See page DI-679.
DTC No.Detection ItemTrouble Area
23

Vehicle speed sensor pulse is abnormal. (When sped signal
is not input to the ECU below 0.2 sec., code will be dis-
played.)
Vehicle speed sensor

Cruise control ECU
WIRING DIAGRAM
See page DI-679.
INSPECTION PROCEDURE
1 Check vehicle speed sensor (See page BE-43).
NG Replace vehicle speed sensor.
OK
Check and replace cruise control ECU
(See page IN-28).
DI4XU-01

I02719
W-B
IEW-BJ/B No.1
1
1J13
1HCruise Control ECU
W-B
W-B13
C16
C14 17
Cruise Control Switch CANCELSET/
COASTRESUME/
ACCEL E
MAIN
CMS15
C14
5
C14R-Y
L19
C16
18
C16GND
W-B
CMS
CCS DI-682
- DIAGNOSTICSCRUISE CONTROL SYSTEM
910 Author
: Date
:
1997 SUPRA (RM502U)
DTC 32 Control Switch Circuit
(Cruise Control Switch)
CIRCUIT DESCRIPTION
This circuit carries the SET/COAST, RESUME/ACCEL and CANCEl signals (each voltage) to the ECU.
DTC No.Detection ItemTrouble Area
32Short in control switch circuit

Cruise control switch

Harness or connector between control switch and cruise
control ECU.

Cruise control ECU
WIRING DIAGRAM
DI4XV-01

Input SignalIndicator Light
Blinking Pattern
SET/COAST
switch
RESUME/ACCEL
switch
CANCEL switch2 Pulses
ON
OFF
ON
OFF3 Pulses
ON
OFFSW OFF
SW ON
N16045
3 4
- DIAGNOSTICSCRUISE CONTROL SYSTEM
DI-683
911 Author
: Date
:
1997 SUPRA (RM502U)
INSPECTION PROCEDURE
1 Input signal check.
PREPARATION:
See input signal check on page DI-662.
CHECK:
Check the indicator light operation when each of the SET/
COAST, RESUME/ACCEL and CANCEL is turned on.
OK:
SET/COAST, RESUME/ACCEL switch
The signals shown in the table on the left should be
output when each switch is ON. The signal should
disappear when the switch is turned OFF.
CANCEL switch
The indicator light goes off when the cancel switch is
turned on.
OK Wait and see.
NG
2 Check control switch.
PREPARATION:
(a) Remove steering wheel center pad (See page SR-1 1).
(b) Disconnect control switch connector.
CHECK:
Measure resistance between terminals 3 and 4 of control switch
connector when control switch is operated.
Switch positionResistance (W)
Neutral8 (No continuity)
RES/ACC50 - 80
SET/COAST180 - 220
CANCEL400 - 440
OK Repair control switch.
NG

DI-684
- DIAGNOSTICSCRUISE CONTROL SYSTEM
912 Author
: Date
:
1997 SUPRA (RM502U)
3 Check harness and connector between cruise control switch and cruise control
ECU (See page IN-28).
NG Repair or replace harness or connector.
OK
4 Input signal check (See step 1).
OK Wait and see.
NG
Check and replace cruise control ECU
(See page IN-28).

I02720
IDL164
E9R-B*
1
R*2
R-B*1
2*2T2
IDL
Throttle Position Sensor3
IJ1R-B21
C16
IDL Cruise Control ECU
3*1
R-B*1
R*2R*2
*1: 2JZ-GE Engine
*2: 2JZ-GTE Engine ECM
- DIAGNOSTICSCRUISE CONTROL SYSTEM
DI-685
913 Author
: Date
:
1997 SUPRA (RM502U)
DTC 51 Idle Signal Circuit
CIRCUIT DESCRIPTION
When the idle switch in turned ON, a signal is sent to the ECU. The ECU uses this signal to correct the dis-
crepancy between the throttle valve position and the actuator position sensor value to enable accurate
cruise control at the set speed. If the idle switch is malfunctioning, problem symptoms also occur in the en-
gine, so also inspect the engine.
DTC No.Detection ItemTrouble Area
51Short in idle signal circuit

Harness or connector between cruise control ECU and
throttle position sensor

Throttle position sensor

Cruise control ECU
WIRING DIAGRAM
DI4XW-01

DI-686
- DIAGNOSTICSCRUISE CONTROL SYSTEM
914 Author
: Date
:
1997 SUPRA (RM502U)
INSPECTION PROCEDURE
1 Check throttle position sensor circuit
(2JZ-GE: See page SF-42, 2JZ-GTE: See page SF-44).
NG Replace throttle position sensor.
OK
2 Check harness and connector between ECM and throttle position sensor
(See page IN-28).
NG Repair or replace harness or connector.
OK
3 Check harness and connector between cruise control ECU and throttle position
sensor (See page IN-28).
NG Repair or replace harness or connector.
OK
Check and replace cruise control ECU
(See page IN-28).

N19613
22
1 2
4
3
10 16Cruise Control ECU
1B
I1 S11
S11G-W
B-W
Cruise Control Actuator R/B No.2
Battery
B 2A2
ALT
W-LJ/B No.1
STOP10
C16
L STP-
2 W-L
S11 S11
C16
POWERR-LR-LWStop Light Switch
- DIAGNOSTICSCRUISE CONTROL SYSTEM
DI-687
915 Author
: Date
:
1997 SUPRA (RM502U)
Stop Light Switch Circuit
CIRCUIT DESCRIPTION
When the brake is on, battery positive voltage normally applies through the STOP fuse and stop light switch
to terminal STP- of the ECU, and the ECU turns the cruise control off.
A fail-safe function is provided so that cancel functions normally, even if there is a malfunction in the stop
light signal circuit.
If the harness connected to terminal STP- has an open circuit, terminal STP- will have battery positive volt-
age and the cruise control will be turned off.
Also, when the brake is on, the magnetic clutch is cut mechanically by the stop light switch, turning the cruise
control off. (See page DI-675 for operation of the magnetic clutch)
WIRING DIAGRAM
DI4XX-01

Input SignalIndicator Light
Blinking Pattern
Stop Light
switch ON
LightOFF
ONSW OFF
SW ON
DI-688
- DIAGNOSTICSCRUISE CONTROL SYSTEM
916 Author
: Date
:
1997 SUPRA (RM502U)
INSPECTION PROCEDURE
1 Check operation of stop light.
CHECK:
Check that stop light comes on when brake pedal is depressed, and turns off when brake pedal is released.
NG Check stop light system.
OK
2 Input signal check.
CHECK:
(a) See input signal check on DI-662.
(b) Check the indicator light when the brake pedal is de-
pressed.
OK:
The indicator light goes off when the brake pedal is
depressed.
OK Proceed to next circuit inspection shown on
problem symptoms table (See page DI-671).
NG

I02722
ON
(-)STP-(+)
- DIAGNOSTICSCRUISE CONTROL SYSTEM
DI-689
917 Author
: Date
:
1997 SUPRA (RM502U)
3 Check voltage between terminal STP- of cruise control ECU connector and body
ground.
PREPARATION:
Remove cruise control ECU with connectors still connected.
CHECK:
(a) Turn ignition switch ON.
(b) Measure voltage between terminal STP-of cruise control
ECU connector and body ground, when the brake pedal
is depressed and released.
OK:
Depressed10 - 14 V
ReleasedBelow 1 V
OK Proceed to next circuit inspection shown on
problem symptoms table (See page DI-671).
NG
4 Check for open in harness and connectors between terminal STP- of cruise con-
trol ECU and stop light switch (See page IN-28).
NG Repair or replace harness or connector.
OK
Check and replace cruise control ECU
(See page IN-28).