Page 741 of 1807

DI7HM-01
W01411
1 2 3 4 5 6
7 8 9 10 11 121 2 3 4 5 6 7 8 9 10 11
12 13 14 15 16 17 18 19 20 21 22 A18
A19
DI-450
- DIAGNOSTICSANTI-LOCK BRAKE SYSTEM
678 Author: Date:
1997 SUPRA (RM502U)
TERMINALS OF ECU
NORMAL ABS (2JZ-GE Engine):
Symbols (Terminal No.)STD Voltage (V)Condition
IG1 (A18-2) - GND (A19-2,13)10 - 14IG switch ON
SR (A19-18) - R+ (A19-8)Below 1.5IG switch ON, ABS warning light OFF
MR (A19-7) - R+ (A19-8)10 - 14IG switch ON
SFRH (A19-4) - GND (A19-2,13)10 - 14IG switch ON, ABS warning light OFF
SFRR (A19-1) - GND (A19-2,13)10 - 14IG switch ON, ABS warning light OFF
SFLH (A19-10) - GND (A19-2,13)10 - 14IG switch ON, ABS warning light OFF
SFLR (A19-11) - GND (A19-2,13)10 - 14IG switch ON, ABS warning light OFF
SRR (A19-22) - GND (A19-2,13)10 - 14IG switch ON, ABS warning light OFF
SRH (A19-21) - GND (A19-2,13)10 - 14IG switch ON, ABS warning light OFF
AST (A19-16) - GND (A19-2,13)10 - 14IG switch ON, ABS warning light OFF
WA (A18 4) GND (A19 2 13)Below 2.0IG switch ON, ABS warning light ONWA (A18-4) - GND (A19-2,13)10 - 14IG switch ON, ABS warning light OFF
STP (A18 12) GND (A19 2 13)Below 1.5Stop light switch OFFSTP (A18-12) - GND (A19-2,13)8 - 14Stop light switch ON
D/G (A18-11) - GND (A19-2,13)10 - 14IG switch ON, ABS warning light OFF
MT (A19-9) - GND (A19-2,13)Below 1.5IG switch ON
Tc (A18-9) - GND (A19-2,13)10 - 14IG switch ON
Ts (A18-8) - GND (A19-2,13)10 - 14IG switch ON
FR+ (A19-3) - FR- (A19-14)AC generationIG switch ON
Slowly turn right front wheel
FL+ (A19-19) - FL- (A19-20)AC generationIG switch ON
Slowly turn left front wheel
RR+ (A18-1) - RR- (A18-7)AC generationIG switch ON
Slowly turn right rear wheel
RL+ (A18-3) - RL- (A18-10)AC generationIG switch ON
Slowly turn left rear wheel
Page 742 of 1807

W02803
1 2 3 4 5
6
7
8
9 10 11
121
2 3 4 5
6 7 8 9
10
11 12 13
14 15 16
17 18
19 20 21 22 A21
A20
23
24 25 26
- DIAGNOSTICSANTI-LOCK BRAKE SYSTEM
DI-451
679 Author: Date:
1997 SUPRA (RM502U)
Sport ABS (2JZ-GTE Engine):
Symbols (Terminal No.)STD Voltage (V)Condition
IG1 (A20-13) - GND (A20-12,25)10 - 14IG switch ON
SR (A21-7) - R+ (A20-26)10 - 14IG switch ON, ABS warning light OFF
MR (A21-1) - R+ (A20-26)Below 1.0IG switch ON
SFRH (A20-2) - GND (A20-12,25)10 - 14IG switch ON, ABS warning light OFF
SFRR (A20-1) - GND (A20-12,25)10 - 14IG switch ON, ABS warning light OFF
SFLH (A21-5) - GND (A20-12,25)10 - 14IG switch ON, ABS warning light OFF
SFLR (A21-6) - GND (A20-12,25)10 - 14IG switch ON, ABS warning light OFF
SRRH (A21-11) - GND (A20-12,25)10 - 14IG switch ON, ABS warning light OFF
SRRR (A21-12) - GND (A20-12,25)10 - 14IG switch ON, ABS warning light OFF
SRLH (A20-15) - GND (A20-12,25)10 - 14IG switch ON, ABS warning light OFF
SRLR (A20-14) - GND (A20-12,25)10 - 14IG switch ON, ABS warning light OFF
AST (A21-4) - GND (A20-12,25)10 - 14IG switch ON, ABS warning light OFF
WA (A20 11) GND (A20 12 25)Below 2.0IG switch ON, ABS warning light ONWA (A20-11) - GND (A20-12,25)10 - 14IG switch ON, ABS warning light OFF
STP (A20 5) GND (A20 12 25)Below 1.5Stop light switch OFFSTP (A20-5) - GND (A20-12,25)8 - 14Stop light switch ON
D/G (A20-24) - GND (A20-12,25)10 - 14IG switch ON, ABS warning light OFF
MT (A21-10) - GND (A20-12,25)Below 1.5IG switch ON
Tc (A20-8) - GND (A20-12,25)10 - 14IG switch ON
Ts (A20-21) - GND (A20-12,25)10 - 14IG switch ON
FR+ (A21-3) - FR- (A21-9)AC generationIG switch ON
Slowly turn right front wheel
FL+ (A21-8) - FL- (A21-2)AC generationIG switch ON
Slowly turn left front wheel
RR+ (A20-10) - RR- (A20-23)AC generationIG switch ON
Slowly turn right rear wheel
RL+ (A20-22) - RL- (A20-9)AC generationIG switch ON
Slowly turn left rear wheel
FRO (A20-7) - GND (A20-12,25)Pulse generationVehicle driving at about 30 km/h (19 mph)
FLO (A20-20) - GND (A20-12,25)Pulse generationVehicle driving at about 30 km/h (19 mph)
RRO (A20-6) - GND (A20-12,25)Pulse generationVehicle driving at about 30 km/h (19 mph)
RLO (A20-19) - GND (A20-12,25)Pulse generationVehicle driving at about 30 km/h (19 mph)
GL1 (A20-4) - GND (A20-12,25)0.5 - 4.5 VIG switch ON
GL2 (A20-16) - GND (A20-12,25)0.5 - 4.5 VIG switch ON
VGS (A20-3) - GND (A20-12,25)4.5 - 5.5 VIG switch ON
Page 743 of 1807

DI4VA-01
DI-452
- DIAGNOSTICSANTI-LOCK BRAKE SYSTEM
680 Author: Date:
1997 SUPRA (RM502U)
PROBLEM SYMPTOMS TABLE
If a normal code is displayed during the DTC check but the problem still occurs, check the circuits for each
problem symptom in the order given in the table below and proceed to the relevant troubleshooting page.
NOTICE:
When removing the ECU, turn the IG switch OFF.
SymptomsInspection CircuitSee page
ABS does not operate.
Only when 1. - 4. are all normal and the problem is still occurring, replace the ABS
ECU.
1. Check the DTC, reconfirming that the normal code is output.
2. IG power source circuit.
3. Speed sensor circuit.
4. Check the ABS actuator with a checker.
If abnormal, check the hydraulic circuit for leakage (See page DI-498).
DI-442
DI-475
DI-469
BR-66 or XXX
ABS does not operate
efficiently.
Only when 1. - 4. are all normal and the problem is still occurring, replace the ABS
ECU.
1. Check the DTC, reconfirming that the normal code is output.
2. Speed sensor circuit.
3. Stop light switch circuit.
4. Check the ABS actuator with a checker.
If abnormal, check the hydraulic circuit for leakage (See page DI-498).
DI-442
DI-469
DI-482
BR-66 or BR-66
ABS warning light
abnormal.1. ABS warning light circuit.
2. ABS ECU.DI-488
DTC check cannot be done.
Only when 1. and 2. are all normal and the problem is still occurring, replace the
ABS ECU.
1. ABS warning light circuit.
2. Tc terminal circuit.
DI-488
DI-494
Speed sensor signal check
cannot be done.1. Ts terminal circuit.
2. ABS ECU.DI-496XXX
Page 771 of 1807
F03338
Deceleration sensor
3
5
1
2
A23
A23
A23
A23B
W-B
W
R
G
W-B
IG IEA20
A20
A20
A20
3
16
4
17VGS
GL2
GL1
GGNDABS ECU DI-480
- DIAGNOSTICSANTI-LOCK BRAKE SYSTEM
708 Author: Date:
1997 SUPRA (RM502U)
DTC 44 Deceleration Sensor Circuit
(SPORT ABS (2JZ-GTE Engine) only)
CIRCUIT DESCRIPTION
This sensor detects deceleration on the vehicle. The sensor signal is used in ABS control. If the sensor func-
tions abnormally, the ABS warning light comes on but the ABS still operates.
DTC No.DTC Detecting ConditionTrouble Area
44
Either of the following (1), (2) or (3) is detected:
(1) IG switch ON and output voltage of GL1 or GL2 remains
0.5 V or less or 4.5 V or more for more than 1.2 sec.
(2) At vehicle speed of 0 km/h, outputs of GL1 and GL2 re-
mains abnormally different for 60 sec. or more
(3) IG switch ON and VGS 4.4 V, VGS 5.5 V continues
for 1.2 sec. or more.
Deceleration sensor
Open or short in deceleration sensor circuit
WIRING DIAGRAM
DI4VH-01
Page 773 of 1807
F03341
R/B No.2J/B No.1Stop Light
SwitchABS ECU
125
Light
Failure
Sensor
Stop LightJ/B
No.11
10IH
IC
A18 A22 *1*2
G-WG-W
G-W1
2 W STOP
210
1B 1I W-LPOWER
22 W
2
2A
ALTR/B No.2
B
Battery
NORMAL ABS (2JZ-GE Engine)
SPORT ABS (2JS-GTE Engine)
*1:
*2:
1
DI-482
- DIAGNOSTICSANTI-LOCK BRAKE SYSTEM
710 Author: Date:
1997 SUPRA (RM502U)
DTC 49 Stop Light Switch Circuit
CIRCUIT DESCRIPTION
This stop light switch senses whether the brake pedal is depressed or released, and sends a signal to the
ECU.
DTC No.DTC Detecting ConditionTrouble Area
491.2 - 1.7 V of STP voltage is continued for 0.3 sec. or more.Open in stop light circuit
WIRING DIAGRAM
INSPECTION PROCEDURE
1 Check operation of stop light.
CHECK:
Check that stop light lights up when brake pedal is depressed and turns off when brake pedal is released.
NG Replace stop light bulb.
OK
DI4VI-01
Page 774 of 1807
F03342F03343F03344
NORMAL ABS (2JZ-GE Engine):
SPORT ABS (2JZ-GTE Engine):V (+)
(-)
(+)
(-)STP
STP
- DIAGNOSTICSANTI-LOCK BRAKE SYSTEM
DI-483
711 Author: Date:
1997 SUPRA (RM502U)
2 Check voltage between terminal STP of ABS ECU and body ground.
PREPARATION:
Remove ABS ECU with connectors still connected.
CHECK:
Measure voltage between terminal STP of ABS ECU and body
ground when brake pedal is depressed.
OK:
Voltage: 8 - 14 V
OK Proceed to next circuit inspection shown on
problem symptoms chart (See page DI-452).
NG
3 Check for open in harness and connector between ABS ECU and stop light
switch (See page IN-28).
NG Repair or replace harness or connector.
OK
Check and replace ABS ECU.
Page 777 of 1807
DI-486
- DIAGNOSTICSANTI-LOCK BRAKE SYSTEM
714 Author: Date:
1997 SUPRA (RM502U)
INSPECTION PROCEDURE
1 Is DTC output?
Check DTC on page DI-442.
YES Repair circuit indicated by the code output.
NO
2 Is normal code displayed?
YES Check ABS solenoid relay. Check for short in
harness and connector between ABS solenoid
relay and DLC1 (See page IN-28).
NO
3 Is ABS warning light go off?
YES Check for open or short in harness and conec-
tor between ECU-IG Fuse and ECU
(See page IN-28).
NO
4 Check battery positive voltage.
PREPARATION:
Start the engine.
CHECK:
Check the battery positive voltage.
OK:
Voltage: 10 - 16 V
NG Check and repair the charging system.
OK
Page 778 of 1807
- DIAGNOSTICSANTI-LOCK BRAKE SYSTEM
DI-487
715 Author: Date:
1997 SUPRA (RM502U)
5 Check ABS warning light.
PREPARATION:
(a) Turn the ignition switch OFF.
(b) Disconnect the conector from the ABS ECU.
(c) Turn the ignition switch ON.
CHECK:
Check the ABS warning light goes off.
OK Check and replace ABS ECU.
NG
Check for short in harness and connector between combination meter and ABS ECU, combina-
tion meter and DLC1 (See page IN-28).