1995 TOYOTA SUPRA traction control

INDICATOR LIGHTS
TroubleParts name (See page) 
 
 SRS Indicator Light does not light up
 
 
 
1. Bulb
2. Wire Harness
3. Center Air Bag Sensor (RS Section)
 
 
 
ABS Indicator Light does not light up
 
 
 
1. Bulb
2. Wire Harness
3. Traction ECU (BR Section)
 
 
 
Malfunction Indicator Light does not light up
 
 
 
1. Bulb
2. ECM (EG Section)
3. Wire Harness
 
 
 
TRAC OFF Indicator Light does not light up
 
 
 
1. Bulb
2. Traction Solenoid Relay (BR Section)
3. Traction ECU (BR Section)
4. Wire Harness
 
 
 
Security Indicator Light does not light up
 
 
 
1. Light Emitting Diode
2. Theft Deterrent and Door Lock ECU (BE±123)
3. Wire Harness
 
 
 
 
A/T Shift Position Indicator Light does not light up
 
 
 
 
1. Bulb
2. Park/Neutral Position Switch (AT1 Section)
3. Light Control Rheostat (BE±54)
4. Meter Circuit Plate (BE±44)
5. Wire Harness
 
 
 
 
MANU Indicator Light does not light up
 
 
 
 
1. Bulb
2. ECM (EG Section)
3. Meter Circuit Plate (BE±44)
4. Wire Harness
 
 
 
 
O/D OFF Indicator Light does not light up
 
 
 
 
1. Bulb
2. O/D Main Switch
3. ECM (EG Section)
4. Meter Circuit Plate (BE±44)
5. Wire Harness
 
 
 
 
TRAC Indicator Light does not light up
 
 
 
 
1. Bulb
2. ABS and Traction ECU
3. Meter Circuit Plate (BE±44)
4. Wire Harness
 
 
 
Turn Indicator Light does not light up
 
 
 
1. Bulb
2. Turn Signal and Hazard Warning System (BE±20)
3. Meter Circuit Plate (BE±44)
4. Wire Harness
 
 
 
 
High Beam Indicator Light does not light up
 
 
 
 
1. Bulb
2. Headlight System (BE±10)
3. Meter Circuit Plate (BE±44)
4. Wire Harness
 
 
 
CRUISE Indicator Light does not light up
 
 
 
1. Bulb
2. Cruise Control ECU (BE±170)
3. Meter Circuit Plate (BE±44)
4. Wire Harness
± BODY ELECTRICAL SYSTEMCOMBINATION METERBE±43

TRAC CONTROL SYSTEM BLEEDING
HINT: When repairing the brake master cylinder or TRAC sys-
tem, bleed the air out of the TRAC system.
1. INSPECT BATTERY POSITIVE VOLTAGE
Battery positive voltage:
10±14 V
2. BLEED TRACTION CONTROL SYSTEM
(a) Disconnect the connector from the TRAC pump.
(b) Connect SST to the TRAC pump.
SST 09990±00330
(c) Connect a vinyl tube to the bleeder plug of the TRAC
actuator, then loosen the bleeder plug.
(d) Start the engine.
(e) Connect the SST to the battery. Then wait at least 60
seconds before tightening the bleeder plug with the TRAC
pump still operating.
Torque: 8.3 NVm (85 kgfVcm, 74 in.Vlbf)
(f) After tightening the bleeder plug, keep the TRAC pump
operating for approximately 30 seconds.
(g) Install the cap.
3. CHECK FLUID LEVEL IN RESERVOIR
Fluid:
SAE J1703 or FMVSS NO. 116 DOT3
4. CLEAR DIAGNOSTIC TROUBLE CODES
(See page BR±127)
± BRAKE SYSTEMCHECK AND ADJUSTMENTBR±9

DTC 15 16 TRAC Solenoid Relay Circuit
CIRCUIT DESCRIPTION
This relay circuit supplies power to each traction actuator solenoid.
When the ignition switch is turned ON, the relay goes on.
 DTC No. Diagnostic Trouble Code Detecting Condition Trouble area 
 
 
 
 
 
 
15
 
 
 
 
 
 
 
Conditions (1) through (3) continue for 0.2
sec. or more:
(1) TRAC solenoid relay terminal (TSR)
voltage: Battery positive voltage
(2) All TRAC actuator solenoids: OFF
(3) All TRAC actuator solenoid monitor
voltages (in ECU): 0 V 
 
 
 
 
 
 

TRAC solenoid relay

Open or short in TRAC solenoid relay circuit

ECU
 
 
 
 
 
 
16
 
 
 
 
 
 
Conditions (1) through (3) continue for 0.2
sec. or more:
(1) TRAC solenoid relay terminal (TSR)
voltage: 0 V
(2) All TRAC actuator solenoids: OFF
(3) TRAC actuator solenoid monitor voltage
(in ECU): Battery positive voltage 
 
 
 
 
 

TRAC solenoid relay

B+ short in TRAC solenoid relay circuit

ECU
Fail safe function: If trouble occurs in this relay circuit, the ECU cuts off current to the ABS and TRAC solenoid
relays and prohibits ABS and TRAC control.
± BRAKE SYSTEMANTI±LOCK BRAKE SYSTEM (ABS)BR±77

TRACTION CONTROL SYSTEM
(TRAC)
TRAC PUMP
COMPONENTS
BR±116± BRAKE SYSTEMTRACTION CONTROL SYSTEM (TRAC)

± BRAKE SYSTEMTRACTION CONTROL SYSTEM (TRAC)BR±117

TRAC PUMP REMOVAL
Installation is in the reverse order of removal.
AFTER INSTALLATION, BLEED BRAKE SYSTEM
(See page BR±7) AND BLEED TRAC SYSTEM (See page
BR±9)
1. REMOVE TRAC ACTUATOR
(See page BR±121)
2. REMOVE BRAKE MASTER CYLINDER
(See page BR±11)
3. DISCONNECT BRAKE LINE
Using SST, disconnect the brake line from the damper.
SST 09023±00100
Torque: 15 NVm (155 kgfVcm, 11 ftVlbf)
4. REMOVE TRAC PUMP ASSEMBLY
Remove the bolt, 2 nuts and TRAC pump assembly.
Torque: 19 NVm (195 kgfVcm, 14 ftVlbf)
5. REMOVE PRESSURE HOSE
Remove the 2 union bolts, 4 O±rings and pressure hose.
Torque: 46 NVm (465 kgfVcm, 34 ftVlbf)
6. REMOVE DAMPER
Remove the 3 bolts, washers, bushings, spacers and damp-
er.
Torque: 7.8 NVm (80 kgfVcm, 69 in.Vlbf)
7. REMOVE TRAC PUMP
Remove the 3 bolts, 2 nuts, washers, TRAC pump bracket
bushings and TRAC pump.
Torque: 7.8 NVm (80 kgfVcm, 69 in.Vlbf)
8. REMOVE TRAC PUMP BRACKET No.2
Remove the 4 bolts and 2 TRAC pump bracket No.2.
Torque: 7.8 NVm (80 kgfVcm, 69 in.Vlbf)
BR±118± BRAKE SYSTEMTRACTION CONTROL SYSTEM (TRAC)

TRAC ACTUATOR
COMPONENTS
± BRAKE SYSTEMTRACTION CONTROL SYSTEM (TRAC)BR±119

BR±120± BRAKE SYSTEMTRACTION CONTROL SYSTEM (TRAC)