1986 TOYOTA SUPRA Tail

P.
EG±489
P. EG±491, P.
EG±493
P.
EG±492
P. IN±24
P.
EG±492
P.
EG±506
P.
EG±494
P.
EG±514
P.
EG±515
P.
EG±505
Vehicle Brought to Workshop
Customer Problem Analysis
Check and Clear Diagnostic Trouble Code (Precheck)
Setting the Test Mode Diagnosis
Problem Symptom Confirmation
Malfunction does not occur
Symptom Simulation
Diagnostic Trouble Code Check
Malfunction code
Diagnostic Trouble Code Chart
Malfunction
occurs
Normal code
Basic Inspection
Matrix Chart of Problem Symptoms
Circuit Inspection
Check for Intermittent problemsParts Inspection
Identification of Problem
Adjustment Repair
Conformation Test
Diagnostic steps permitting the use of
the TOYOTA hand±held tester or
TOYOTA break±out box.
Titles insideare titles of pages
in this manual, with the page number
indicated in the bottom portion.
See the indicated pages for de-
tailed explanations.
HOW TO PROCEED WITH TROUBLESHOOTING
Troubleshoot in accordance with the procedure on the following pages. EG±488
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

Diagnosis Inspection (Normal Mode)
MALFUNCTION INDICATOR LAMP CHECK
1. The Malfunction Indicator Lamp will come on when the
ignition switch is turned ON and the engine is not running.
HINT: If the malfunction indicator lamp does not light up, pro-
ceed to troubleshooting of the telltale light RH (See page
BE±48).
2. When the engine is started, the malfunction indicator lamp
should go off.
If the light remains on, the diagnosis system has detected a
malfunction or abnormality in the system.
DIAGNOSTIC TROUBLE CODE CHECK
1. Turn ignition switch ON.
2. Using SST, connect terminals between TE1 and E1 of data
link connector 1 or 2.
SST 09843±18020
3. Read the diagnostic trouble code from malfunction indicator
lamp.
HINT: If a diagnostic trouble code is not output, check the TE1
terminal circuit (See page EG±598).
As an example, the blinking patterns for codes; normal, 12
and 31 are as shown on the illustration.
4. Check the details of the malfunction using the diagnostic
trouble code table on page EG±494.
5. After completing the check, disconnect terminals TE1 and
E1, and turn off the display.
HINT: In the event of 2 or more malfunction codes, indication
will begin from the smaller numbered code and continue in
order to the larger.
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±491

DIAGNOSTIC TROUBLE CODE CHECK
USING TOYOTA HAND±HELD TESTER
1. Hook up the TOYOTA hand±held tester to the DLC2.
2. Read the diagnostic trouble codes by following the prompts
on the tester screen.
Please refer to the TOYOTA hand±held tester operation's manual
for further details.
DIAGNOSTIC TROUBLE CODE
CLEARANCE
1. After repair of the trouble areas, the diagnostic trouble code
retained in the ECM memory must be cleared out by
removing the EFI No.1 fuse (30A) from R/B No.2 for 10
seconds or more, with the ignition switch OFF.
HINT:
wCancellation can also be done by removing the negative
(±) terminal cable from the battery, but in this case, other
memory systems (clock, etc.) will also be cancelled out.
wIf it is necessary to work on engine components
requiring removal of the negative (±) terminal cable from
the battery, a check must first be made to see if a
diagnostic trouble code has been recorded.
2. After cancellation, road test the vehicle to check that a normal
code is now read on the malfunction indicator lamp.
If the same diagnostic trouble code appears, it indicates that
the trouble area has not been repaired thoroughly.
ECM DATA MONITOR USING TOYOTA
HAND±HELD TESTER
1. Hook up the TOYOTA hand±held tester to the DLC2.
2. Monitor the ECM 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 TOYOTA hand±held tester operator's manual for
further details.
ECM TERMINAL VALUES
MEASUREMENT USING TOYOTA
BREAK±OUT±BOX AND TOYOTA
HAND±HELD TESTER
1. Hook up the TOYOTA break±out±box and TOYOTA
handheld tester to the vehicle.
2. Read the ECM input/output values by following the prompts
on the tester screen.
HINT: TOYOTA hand±held tester has a ºSnapshotº function. This
records the measured values and is effective in the diagnosis of
intermittent problems.
Please refer to TOYOTA hand±held tester/TOYOTA break±out±
box operator's manual for further details.
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±493

 Symbols (Terminals No.) STD Voltage (V) Condition
 EGR (B75) E01 (B80) Below 2.0 Idling
 EGR (B75)±E01 (B80) 9 ~ 14 Engine speed at 3,500 rpm
 VG (B66)±E21 (B28) 0.7 ~ 1.7 Idling
 
 
ISC1 (B35), ISC2 (B34)
Ð E01 (B80)
ISC3 (B33), ISC4 (B32) 
 
Pulse generation
(See page EG±586) 
 Idling when A/C switch ON or OFF
 
VF1 (B29)±E1 (B69) 

1.8 ~ 3.2 

Maintain engine speed at 2,500 rpm for 2
minutes after warming up then return to Idling
 
 OX1 (B48), OX2 (B47)±E1 (B69)
 
 Pulse generation
(See page EG±529)
 
 Maintain engine speed at 2,500 rpm for 2
minutes after warming up
 
HT1 (B71) HT2 (B72) E01 (B80)
 Below 3.0 Idling HT1 (B71), HT2 (B72)±E01 (B80) 9 ~ 14 IG switch ON 
 KNK1 (B50), KNK2 (B49)±E1 (B69)
 
 Pulse generation
(See page EG±563) 
 Idling
 
 
NSW (B76) E1 (B69)
 
 9 ~ 14
 
 IG switch ON
Other shift position in ºPº, ºNº position
 
 
NSW (B76)±E1 (B69) 
 0 ~ 3.0
 
 IG switch ON
Shift position in ºPº, ºNº position
 
 SP1 (A2)±E1 (B69)
 
 
Pulse generation
(See page EG±556) 
 
IG switch ON
Rotate driving wheel slowly
 TE1 (A20)±E1 (B69) 9 ~ 14 IG switch ON
 TE2 (A19)±E1 (B69) 9 ~ 14 IG switch ON
 W (A6)±E1 (B69) 9 ~ 14 Idling
  0 ~ 3.0 IG switch ON
 OD1 (A12)±E1 (B69) 9 ~ 14 IG switch ON
 A/C (A34)±E1 (B69) 7.5 ~14 A/C switch OFF
  0 ~ 1.5 A/C switch ON (At idling)
 ACMG (A23)±E1 (B69) 0 ~ 3.0 A/C switch ON (At idling)
  9 ~ 14 A/C switch OFF
 FPU (B73)±E01 (B80) 9 ~ 14 IG switch ON
  Below 2.0 Restarting at high engine coolant temp.
 ELS (A15)±E1 (B69) 7.5 ~ 14 Defogger switch and taillight switch ON
  0 ~ 1.5 Defogger's switch and taillight switch OFF
 VSV1 (B40)±E1 (B69) Below 3.0 Immediately after racing
  9 ~ 14 Idling
 VSV2 (B39)±E1 (B69) Below 3.0 For 2 sec. after IG switch ON to OFF
  9 ~ 14 Idling
 VSV3 (B38)±E1 (B69) 9 ~ 14 Idling
 
 
 PMC (B60)±E1 (B69)
 
 
 
Below 3.0
 
 
 
Idling (for M/T)
Idling and shift position ºPº, ºNº position
(for AT)
 

PMC (B60)±E1 (B69)
 

9 ~ 14 

Idling and other shift position ºPº, ºNº
position (for A/T))
 
PM1 (B62)±E2 (A65)
 
2.3 ~ 3.0
 
IG switch ON 
 
 
 1.8 ~ 2.4
 
 IG switch ON and apply vacuum 26.7 kPa
(200 mmHg, 7.9 in Hg)
EG±512± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

REFERENCE VALUE OF ECM DATA
HINT: ECM data can be monitored by TOYOTA hand±held
tester.
1. Hook up the TOYOTA hand±held tester to DLC2.
2. Monitor ECM data by following the prompts on the tester
screen.
Please refer to the TOYOTA hand±held tester operator's manual
for further details.
REFERENCE VALUE 
 Item
 
 Inspection condition
 
 Reference value
 
 INJECTOR 
 
Engine cold to hot
Engine idling at normal operating temp.*1
 
 
Gradually decreases
Approx. 1.8 msec.
 IGNITION Increase engine speed Gradually increases
 
 
 
 
IAC STEP #
 
 
 
 
Engine idling at normal operating temp..*1
A/C switch ON
A/T shifting in ºDº position
Ignition switch ON (Engine off)
 
 
 
 
20 ~ 30 steps
Step increases
Step increases
Approx. 125 steps`
 ENGINE SPEED RPM kept stable (Comparison with tachometer) No great changes
 
 MAF
 
 Engine idling at normal operating temp..*1
Increase engine speed
 
 Approx. 3.8 g/s
Gradually increases
 ECT Engine at normal operating temp. 75±95°C (185±203°F).*2 
 
 THROTTLE
 
 
 
Closed throttle position
Wide open throttle
From closed throttle position to wide open throttle
 
 
 
Below 5°
Above 70°
Gradually increases 
 
 
VEHICLE SPD
 
 
 
During driving
(Comparison with speedometer)
 
 
 
No large differences
 TARGET A/FL Engine idling at normal operating temp. 2.50 + 1.25 V*3
 A/F FB LEFT RPM stable at 2,500 rpm with normal operating temp. ON
 KNOCK FB Depress throttle pedal suddenly during idling ON 
 STA SIGNAL 
 During cranking 
 ON
 CTP SIGNAL Closed throttle position ON
 A/C SIGNAL A/C switch ON ON
 
 PNP SIGNAL.*4 
 
When shifting from ºPº or ºNº position into a position
other than ºPº or ºNº 
 GEAR
 OxL RPM stable at 2,500 rpm with normal operating temp. RICH LEAN is repeated
*1: All accessories and A/C switched OFF
*
2: If the engine coolant temp. sensor circuit is open or shorted, the ECM assumes an engine coolant temp.
value of 80°C (176°F).
*
3: When feedback control is forbidden, 0 V is displayed.
*
4: A/T only
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±513

P. EG±783
P. EG±785, P. EG±387
P. EG±386
P. IN±24
P. EG±386
P. EG±400P. EG±388
P. EG±408
P. EG±409
P. EG±399
Vehicle Brought to Workshop
Customer Problem Analysis
Check and Clear Diagnostic Trouble Code (Precheck)
Setting the Test Mode Diagnosis
Problem Symptom Confirmation
Malfunction does not occur.
Malfunction
occur.Symptom Simulation
Diagnostic Trouble Code Check
Malfunction codeNormal code
Basic Inspection
Matrix chart of Problem Symptoms
Circuit Inspection
Parts Inspection
Confirmation Test
Adjustment, Repair
Identification of Problem
Step [2], [3], [6], [11], [14]: Diagnostic steps permitting the use of
the TOYOTA hand±held tester
or TOYOTA break±out±box.
Titles insideare titles of pages
in this manual, with the page number
indicated in the bottom portion.
See the indicated pages for detailed
explanations.
Diagnostic Trouble Code Chart
Check for intermittent problems
HOW TO PROCEED WITH TROUBLESHOOTING
Troubleshoot in accordance with the procedure on the following pages. EG±382
± ENGINE2JZ±GE ENGINE TROUBLESHOOTING

Diagnosis Inspection (Normal Mode)
MALFUNCTION INDICATOR LAMP
CHECK
1. The Malfunction Indicator Lamp will come on when the
ignition switch is turned ON and the engine is not running.
HINT: If the malfunction indicator lamp does not light up, pro-
ceed to troubleshooting of the telltale light RH
(See page BE±48).
2. When the engine is started, the malfunction indicator lamp
should go off.
If the light remains on, the diagnosis system has detected a
malfunction or abnormality in the system.
DIAGNOSTIC TROUBLE CODE CHECK
1. Turn ignition switch ON.
2. Using SST, connect terminals between TE1 and E1 of data
link connector 1 or 2.
SST 09843±18020
3. Read the diagnostic trouble code from malfunction indicator
lamp.
HINT: If a diagnostic trouble code is not output, check the TE1
terminal circuit (See page EG±484).
As an example, the blinking patterns for codes; normal, 12
and 31 are as shown on the illustration.
4. Check the details of the malfunction using the diagnostic
trouble code table on page EG±388.
5. After completing the check, disconnect terminals TE1 and
E1, and turn off the display.
HINT: In the event of 2 or more malfunction codes, indication
will begin from the smaller numbered code and continue in
order to the larger.
± ENGINE2JZ±GE ENGINE TROUBLESHOOTINGEG±385

DIAGNOSTIC TROUBLE CODE CHECK
USING TOYOTA HAND±HELD TESTER
1. Hook up the TOYOTA hand±held tester to the DLC2.
2. Read the diagnostic trouble codes by following the prompts
on the tester screen.
Please refer to the TOYOTA hand±held tester operation's
manual for further details.
DIAGNOSTIC TROUBLE CODE CLEARANCE
1. After repair of the trouble areas, the diagnostic trouble code
retained in the ECM memory must be cleared out by
removing the EFI No.1 fuse (30A) from R/B No.2 for 10
seconds or more, with the ignition switch OFF.
HINT:
wCancellation can also be done by removing the negative
(±) terminal cable from the battery, but in this case, other
memory systems (clock, etc.) will also be cancelled out.
wIf it is necessary to work on engine components
requiring removal of the negative (±) terminal cable from
the battery, a check must first be made to see if a
diagnostic trouble code has been recorded.
2. After cancellation, road test the vehicle to check that a normal
code is now read on the malfunction indicator lamp.
If the same diagnostic trouble code appears, it indicates that
the trouble area has not been repaired thoroughly.
ECM DATA MONITOR USING TOYOTA
HAND±HELD TESTER
1. Hook up the TOYOTA hand±held tester to the DLC2.
2. Monitor the ECM 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 TOYOTA hand±held tester operator's manual for
further details.
ECM TERMINAL VALUES MEASUREMENT
USING TOYOTA BREAK±OUT±BOX AND
TOYOTA HAND±HELD TESTER
1. Hook up the TOYOTA break±out±box and TOYOTA
handheld tester to the vehicle.
2. Read the ECM input/output values by following the prompts
on the tester screen.
HINT: TOYOTA hand±held tester has a ºSnapshotº function. This
records the measured values and is effective in the diagnosis of
intermittent problems.
Please refer to TOYOTA hand±held tester/TOYOTA break±out
box operator's manual for further details.
± ENGINE2JZ±GE ENGINE TROUBLESHOOTINGEG±387