1995 TOYOTA SUPRA traction control

TRAC ACTUATOR 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. DISCONNECT BRAKE LINES
Using SST, disconnect the brake lines from the TRAC actua-
tor.
SST 09751±36011
Torque: 15 NVm (155 kgfVcm, 11 ftVlbf)
2. REMOVE TRAC ACTUATOR ASSEMBLY
Remove the 2 bolts, nut and TRAC actuator assembly.
Torque: 13 NVm (130 kgfVcm, 9 ftVlbf)
3. REMOVE TRAC ACTUATOR
Remove the 3 bolts and actuator from the bracket.
Torque: 13 NVm (130 kgfVcm, 9 ftVlbf)
4. SEPARATE TRAC ACTUATOR BRACKET
Remove the 2 bolts and separate the bracket.
Torque: 13 NVm (130 kgfVcm, 9 ftVlbf)
± BRAKE SYSTEMTRACTION CONTROL SYSTEM (TRAC)BR±121

±MEMO± BR±122
± BRAKE SYSTEMTRACTION CONTROL SYSTEM (TRAC)

TROUBLESHOOTING
± BRAKE SYSTEMTRACTION CONTROL SYSTEM (TRAC)BR±123

P. BR±125
P. BR±126 ~ BR±128
P. BR±24
P. BR±126
P. BR±128P. BR±133
P. BR±165P. BR±134 ~ P. BR±163
Vehicle brought to workshop
Customer Problem Analysis
Check and Clear Diagnostic Trouble Codes (Precheck)
Problem Symptom ConfirmationSymptom Simulation
Diagnostic Trouble Code Check
Diagnostic Trouble Code ChartProblem Symptoms Chart
Check for Fluid LeakageCircuit InspectionSensor Check
Identification of Problem
Repair
Confirmation Test
Items insideare titles of pages in this manual,
with the page number in the bottom portion. See the
pages for detailed explanation.
Perform troubleshooting in accordance with the procedure on the following pages.
EndStep [2] , [5] , [9] , [11] : Diagnostic steps permitting the use
of the TOYOTA hand±held tester.
Symptom
does not occur
Symptom
occurs
Normal code
HOW TO PROCEED WITH TROUBLESHOOTING
BR±124± BRAKE SYSTEMTRACTION CONTROL SYSTEM (TRAC)

CUSTOMER PROBLEM ANALYSIS CHECK SHEET
 
 TRAC Check Sheet
Inspector 's
Name:
   Registration No. 
 
 Customer 's Name
 
 
 
 Registration Year
 
 //
 
 
 
 
 
 Frame No. 
 
 
 
Date Vehicle
Brought In 
 // 
 Odometer Reading 
 
km
Miles
 
 
 
Date Problem First Occurred
 
 
 
//
 
  Frequency Problem Occurs 
  Continuous  Intermittent ( Times a day)

 
 
 
 TRAC does not operate. (Wheels spin when starting rapidly).
 
 
  Symptoms
 
 
 
TRAC Indicator
Light Abnormal
 
 
 Remains ON Blinks Does not Light Up
 
 
 
 
 
 
TRAC OFF Indicator
Light Abnormal
 
 
 
Remains ON Does not Light Up
 
 
Ch k It
 
 ABS Warning LIght 
 Normal Malfunction Code (Code )
 
 
Check Item 
 
Malfunction
Indicator Lamp 
 NormalMalfunction Code (Code )
 
 Diagnostic
Tro ble Code
 
 1st Time
 
 Normal CodeMalfunction Code (Code )
 
 
 
Trouble Code
Check 
 
 
2nd Time
 
 
 
Normal CodeMalfunction Code (Code )
± BRAKE SYSTEMTRACTION CONTROL SYSTEM (TRAC)BR±125

DIAGNOSIS SYSTEM
INDICATOR CHECK
When the ignition switch is turned ON, check that the TRAC
indicator light goes on for 3 seconds.
HINT: If the indicator check result is not normal, proceed to
troubleshooting for the TRAC indicator light circuit (See page
BR±162).
DIAGNOSTIC TROUBLE CODE CHECK
1. Turn the ignition switch ON.
2. Using SST connect terminals Tc and E1 of DLC2 or DLC1.
SST 09843±18020
3. Read the diagnostic trouble code from the TRAC indicator
light on the combination meter.
HINT: If no code appears, inspect the diagnostic circuit or
TRAC indicator light circuit (See page BR±162 or BR±163)
As an example, the blinking patterns for normal code and
code 32 are shown on the left.
4. Codes are explained in the code table on page BR±128.
5. After completing the check, disconnect terminals Tc and E1,
and turn off the display.
If 2 or more malfunctions are indicated at the same time, the
lowest numbered diagnostic trouble code will be displayed
first.
ECU DATA MONITOR USING TOYOTA
HAND±HELD TESTER
1. Hook up the TOYOTA hand±held tester to the DLC2
2. Monitor the ECU data by following the prompts on the tester
screen.
HINT: TOYOTA hand±held tester has a ºSnapshotº function
which records the monitored data.
Please refer to the TOYOTA hand±held tester operator's
manual for further details. BR±126
± BRAKE SYSTEMTRACTION CONTROL SYSTEM (TRAC)

DIAGNOSTIC TROUBLE CODE
CLEARANCE
1. Using SST, connect terminals Tc and E1 of DLC2 or DLC1.
SST 09843±18020
2. IG switch ON.
3. Clear the diagnostic trouble codes stored in ECU by
depressing the brake pedal 8 or more times within 3 seconds.
4. Check that the TRAC indicator light shows the normal code.
5. Remove the SST from the terminals of DLC2 or DLC1.
HINT: Cancellation can also be done by removing the ECU±B
fuse, but in this case, other memory systems will also be can-
celled out.
± BRAKE SYSTEMTRACTION CONTROL SYSTEM (TRAC)BR±127

BR±134
BR±137
BR±137
BR±138
BR±138
BR±138
BR±138
BR±142
BR±145
BR±147
BR±149
BR±149
BR±152
BR±152
BR±155
BR±156
BR±157
Open or short in sub±throttle actuator circuit
Step motor does not move to a position decided by ECU
Sub±throttle valve does not move even when the sub±throttle
valve is controlled to fully open position by ECU
Right front wheel speed sensor signal malfunction
Left front wheel speed sensor signal malfunction
Right rear wheel speed sensor signal malfunction
Left rear wheel speed sensor signal malfunction
Low battery positive voltage or abnormally high battery
positive voltage
Malfunction in ABS or TRAC (BRAKE) control system
Open or short in NE signal circuit
Main throttle position sensor circuit malfunction
Open or short in main throttle position sensor circuit
Sub±throttle position sensor circuit malfunction
Open or short in sub±throttle position sensor circuit
Engine & ECT system malfunction
ECM communication circuit malfunction
ABS & TRAC ECU communication circuit malfunction
Malfunction in TRAC ECU
DiagnosisCodeTRAC Indicator Light
Blinking PatternSee page
DIAGNOSTIC TROUBLE CODE CHART
If a malfunction code is displayed during the diagnostic trouble code check, check the circuit listed for that code
in the table below and proceed to the relevant page.
HINT: If the TRAC indicator light lights up and the TRAC indicator light does not blink when the DTC is checked,
check the blinking pattern of the ABS warning light and troubleshoot the ABS system.
*
1: If a malfunction is detected in ABS the TRAC OFF indicator light lights up instead of the TRAC indicator
light.
*
2: The TRAC indicator light does not light up even if an error is detected
*3: If a malfunction is detected, the TRAC OFF indicator light lights up instead of the TRAC indicator light.
*4: Depending on the malfunction, the TRAC indicator light does not light up. BR±128
± BRAKE SYSTEMTRACTION CONTROL SYSTEM (TRAC)