1986 TOYOTA SUPRA Service Repair Manual

DTC
No.
Number of
MIL BlinksCircuitDiagnostic Trouble Code Detecting Condition
(1) Open or short in heater circuit of main heated oxygen
sensor (Fr) for 0.5 sec. or more.
(2) Main heated oxygen sensor (Fr) signal voltage is reduced to
between 0.35 V and 0.70 V for 90 sec. under conditions
Main Heated
Oxygen Sensor
Signal(a) ~ (d):
(2 trip dectection logic)*3
(a) Engine coolant temp.: Between 80°C (176°F) and
95°C (203°F)
(b) Engine speed: 1,500 rpm or more
(c) Load driving (Example A/T in Overdrive, (5th for
M/T), A/C ON, Flat road, 80 km/h (50 mph)
(d) Main heated oxygen sensor signal voltage:
Alternating above and below 0.45 V
Open or short in engine coolant temp. sensor circuit for 0.5
sec. or more
Open or short in intake air temp. sensor circuit for 0.5 sec.
or more
(1) Main heated oxygen sensor voltage is 0.45 V or less (lean)
for 90 sec. under conditions (a) and (b):
(2 trip dectection logic)*3
(a) Engine speed: 1,500 rpm or more
(b) Engine coolant temp.: 70°C or more
(a) Engine speed: Below 950 rpm
(b) Engine coolant temp.: 80°C (176°F) or more
(2 trip dectection logic)*4
(2) Engine speed varies by more than 20 rpm over the preced±
ing crank angle period during a period of 20 sec. or more
under conditions (a) and (b):
Intake Air
Temp. Sensor
Signal
Engine Coolant
Temp. Sensor
Circuit
Air±Fuel
Ratio Lean
Malfunction
*3: See page EG±503. EG±496
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

 
 
 Trouble Area
 
 
 
Malfunction
Indicator
Lamp*
1
 
 
 Memory*2
 
 
 See page
 
 
Trouble Area
 
 
Normal
Mode 
 
Test
Mode 
 
Memory
 
 
See page
 
 
 
 

Open or short in heater circuit of main heated oxygen
sensor

Main heated oxygen sensor heater

ECM
 
 
 
 
ON
 
 
 
 
N.A.
 
 
 
 
 
 
 
 
 
 
 
 
Main heated oxygen sensor circuit
Mi h td
 
 
 
 ON
 
 
 
 ON
 
 
 
 

 
 
 
 
EG±525

Main heated oxygen sensor
ON

ON
 Main heated oxygen sensor    
     
     
 
 
 

Open or short in engine coolant temp. sensor circuit

Engine coolant temp. sensor

ECM
 
 
 ON
 
 
 ON
 
 
 
 
 
 EG±530
 
 
 

Open or short in intake air temp. sensor circuit

Intake air temp. sensor

ECM
 
 
 ON
 
 
 ON
 
 
 
 
 
 EG±532
 
Open or short in Main heated oxygen sensor circuit    
 Oen or short in Main heated oxygen sensor circuit

Main heated oxygen sensor    
 Main heated oxygen sensor

Ignition system    
 
gy

ECM    
 
Open or short in injector circuit    
 
Oen or short in injector circuit

Fuel linepressure (injector leak blockage) ON ON  EG 534

Fuel line pressure (injector leak, blockage)

Mechanical system malfunction (skipping teeth ofONONEG±534 
Mechanical system malfunction (skipping teeth of
timing belt)    
 timing belt)

Ignition system
    
 
Ignition system

Compression pressure (foreign object caught in valve)
    
 
Compression pressure (foreign object caught in valve)
M i fl t (i itk)    
 
Mass air flow meter (air intake)
ECM    

ECM
*1, 2: See page EG±502
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±497

DTC
No.
Number of
MIL BlinksCircuitDiagnostic Trouble Code Detecting Condition
(a) Engine speed: Below 950 rpm
(b) Engine coolant temp.: 80°C (176°F) or more
(2 trip dectection logic)*3
Engine speed varies by more than 20 rpm over the preceding
crank angle period during a period of 25 sec. or more
under conditions (a) and (b):
(1) Open or short in heater circuit of sub heated oxygen sensor
for 0.5 sec. or more
(2) Main heated oxygen sensor signal is 0.45 V or more and
sub heated oxygen sensor signal is 0.45 V or less under
conditions (a) ~ (c):
(2 trip dectection logic)*3
(a) Engine coolant temp.: 80°C (176°F) or more
(b) Engine speed: 1,5000 rpm or more
(c) Accel. pedal: Fully depressed for 2 sec. or more
Open or short in mass air flow meter circuit for 3 sec. or more
with engine speed less than 3,000 rpm
Open or short in turbo pressure sensor circuit for 0.5 sec. or
more
Open or short in BARO sensor circuit for 0.5 sec. or more
Sub Heated
Oxygen Sensor
Signal
Air±Fuel
Ratio Rich
Malfunction
Mass Air Flow
Meter Circuit
Turbo Pressure
Malfunction
Turbo Pressure
Sensor Circuit
Barometric
Pressure
Sensor Circuit
(c) Engine speed: 2,4000 rpm or more
(a) Mainfold absolute pressure: 200 kPa (2.0 kgf/cm2,
29 psi) or more
(b) Thottle valve opening angle: 20° or more
All conditions below are detected continuously for 2 sec. or more:
*3: See page EG±503. EG±498
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

 
 
 Trouble Area
 
 
 
Malfunction
Indicator
Lamp*
1
 
 
 Memory*2
 
 
 See page
 
 
Trouble Area
 
 
Normal
Mode 
 
Test
Mode 
 
Memory
 
 
See page
 
 
 
 
 
 
 
 

Open or short in injector circuit

Fuel line pressure (injector leak, blockage)

Mechanical system malfunction (skipping teeth of
timing belt)

Ignition system

Compression pressure (foreign object caught in valve)

Mass air flow meter (air intake)

ECM
 
 
 
 
 
 
 
 
ON
 
 
 
 
 
 
 
 
ON
 
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
EG±534
 
 
 
 

Open or short in heater circuit of sub heated oxygen
sensor.

Sub heated oxygen sensor

ECM
 
 
 
 
ON
 
 
 
 
N.A.
 
 
 
 
 
 
 
 
 
 
 
 
 

Open or short in sub heated oxygen sensor circuit

Sub heated oxygen sensor

ECM
 
 
 
 
 
ON
 
 
 
 
 
ON
 
 
 
 
 
 
 
 
 
 
EG±540
 
 
 

Open or short in mass air flow meter circuit

Mass air flow meter

ECM
 
 
 ON
 
 
 N.A.
 
 
 
 
 
 EG±544
 
 
 
 
 

Actuator (for waste gate valve)

Short in VSV for waste gate valve circuit

ECM
 
 
 
 
 
ON
 
 
 
 
 
N.A.
 
 
 
 
 

 
 
 
 
 
EG±546
 
 
 

Open or short in turbo pressure sensor circuit

Turbo pressure sensor

ECM
 
 
 ON
 
 
 ON
 
 
 
 
 
 EG±549
 
 
 

ECM
 
 
 
ON
 
 
 
ON
 
 
 
 
 
 
EG±549
*1, 2: See page EG±502.
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±499

DTC
No.
Number of
MIL BlinksCircuitDiagnostic Trouble Code Detecting Condition
No starter signal to ECM
Open or short in throttle position sensor circuit for 0.5 sec. or
more
Engine control computer (for knock control) malfunction at
engine speed between 650 rpm and 5,200 rpm
(c) Park/neutral position switch: OFF
(d) Stop light switch: OFF
(a) No. 1 vehicle speed signal: 0 km/h (mph)
(b) Engine speed: 3,000 or more
All conditions below are detected continuously for 8 sec. or more:
(a) No. 1 vehicle speed signal: 0 km/h (mph)
(b) Engine speed: Between 1,500 rpm and 4,000 rpm
All conditions below are detected continuously for 8 sec. or more:
(c) Engine coolant temp.: 80°C (176°F) or more
(d) Load driving
Open or short in sub±throttle position sensor circuit for 0.5 sec.
or more
No No.2 knock sensor signal to ECM for 4 crank revolutions
with engine speed between 2,050 rpm and 5,950 rpm
No No.1 knock sensor signal to ECM for 4 crank revolutions
with engine speed between 2,050 rpm and 5,950 rpmKnock Sensor
Signal
(front side)
Knock Sensor
Signal
(rear side)
Knock Control
Signal
Sub±Throttle
Position Sensor
Signal
No. 1 Vehicle
Speed Sensor
Signal
(for A/T)
No. 1 Vehicle
Speed Sensor
Signal
(for M/T)
Starter Signal
Throttle Position
Sensor Signal
EG±500± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

 
 
 Trouble Area
 
 
 
Malfunction
Indicator
Lamp*
1
 
 
 Memory*2
 
 
 See page
 
 
Trouble Area
 
 
Normal
Mode 
 
Test
Mode 
 
Memory
 
 
See page
 
 
 

Open or short in throttle position sensor circuit

Throttle position sensor

ECM
 
 
 
ON
 
 
 
ON
 
 
 

 
 
 
EG±552
 
 
 
 
 
 
 
 
 

No.1 vehicle speed sensor

Telltale light RH

Open or short in No.1 vehicle speed sensor circuit

ECM
 
 
 
 
 
 
 
 
 
OFF
 
 
 
 
 
 
 
 
 
OFF
 
 
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
 
EG±556
 
 
 

Open or short in starter signal circuit

Open or short in ignition switch or starter relay circuit

ECM
 
 
 
N.A
 
 
 
OFF
 
 
 
X
 
 
 
EG±559
 
 
 

Open or short sub±throttle position sensor circuit

Sub±throttle position sensor

ECM
 
 
 
OFF
 
 
 
ON
 
 
 

 
 
 
EG±552
 
 
 

Open or short in No.1 knock sensor circuit

No.1 Knock sensor (loosensess)

ECM
 
 
 
ON
 
 
 
N.A
 
 
 

 
 
 
EG±561
 
 
 

ECM
 
 
 
ON
 
 
 
N.A
 
 
 
X
 
 
 
EG±561
 
 
 

Open or short in No.2 knock sensor circuit

No.2 Knock sensor (looseness)

ECM
 
 
 
ON
 
 
 
N.A
 
 
 

 
 
 
EG±561
*1,
2: See page EG±502.
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±501

DTC
No.
Number of
MIL BlinksCircuitDiagnostic Trouble Code Detecting Condition
(a) Engine coolant temp.: 60°C (140°F) or more
(2 trip dectection logic)*3
(2 trip dectection logic)*3
(2 trip dectection logic)*3
EGR gas temp. and intake air temp. are 60°C (140°F) or less
for A/T, 55°C (131°F) or less for 1 ~ 4 min. under conditions
(a) and (b):
Fuel Pump
Control Signal
(2 trip dectection logic)*3
(b) EGR operation possible (Example A/T in 3rd speed (5th for
M/T), A/C ON, 96 km/h (60 mph), Flat road)
Switch Condition
Signal
EGR System
Malfunction
(2) Open in input circuit for 1 sec. or more with engine speed
1,000 rpm or less
(1) Open or short in fuel pump circuit for 1 sec. or more with
engine speed 1,000 rpm or less
(3) Open or short in diagnostic signal line (DI) fuel pump ECU
with engine speed 1,000 rpm or less
(1) 3 sec. or more after engine starts, with closed throttle posi±
tion switch OFF (IDL1)
(2) Park/neutral position switch: OFF
(Shift position in ''R'', ''D'', ''2'', or ''L'' position)
(3) A/C switch ON
*1: ºONº displayed in the diagnostic mode column indicates that the Malfunction Indicator Lamp is lit up when
a malfunction is defected. ºOFFº indicates that the ºCHECKº does not light up during malfunction diag±
nosis, even if a malfunction is detected. ºN.A.º indicates that the item is not included in malfunction diag±
nosis.
*2: ºº in the memory column indicates that a diagnostic trouble code is recorded in the ECM memory when
a malfunction occurs. ºXº indicates that a diagnostic trouble code is not recorded in the ECM memory even
if a malfunction occurs. Accordingly, output of diagnostic results in normal or test mode is done with the
IG switch ON. EG±502
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

Malfunction detection (1st time)
(temporarily recorded)Malfunction detection (2nd time)
(MIL lights up)
 
 
 Trouble Area
 
 
 
Malfunction
Indicator
Lamp*
1
 
 
 Memory*2
 
 
 See page
 
 
Trouble Area
 
 
Normal
Mode 
 
Test
Mode 
 
Memory
 
 
See page
 
 
 
 
 
 

Open in EGR gas temp. sensor circuit

Short in VSV circuit for EGR

EGR hose disconnected, valve stuck

Clogged EGR gas passage

ECM
 
 
 
 
 
 
ON
 
 
 
 
 
 
ON
 
 
 
 
 
 

 
 
 
 
 
 
EG±564
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Open or short in fuel pump ECU circuit

Fuel pump ECU

Fuel pump

ECM power source circuit

ECM
 
 
 
 
 
 
 
 
 
 
 
 
 
 
OFF
 
 
 
 
 
 
 
 
 
 
 
 
 
 
ON
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
EG±568
 
 
 
 
 
 

A/C switch circuit

Throttle position sensor IDL circuit

Park/neutral position switch circuit

Accelerator pedal and cable

ECM
 
 
 
 
 
 
N.A.
 
 
 
 
 
 
OFF
 
 
 
 
 
 
X
 
 
 
 
 
 
EG±571
*3: This indicates items for which º2 trip detection logicº is used. With this logic, when a logic malfunction is
first detected, the malfunction is temporarily stored in the ECM memory. If the same case is detected again
during the second drive test, this second detection causes the Malfunction Indicator Lamp to light up.
The 2 trip repeats the same mode a 2nd time. (However, the IG switch must be turned OFF between the
1st trip and 2nd trip).
In the Test Mode, the Malfunction Indicator Lamp lights up the 1st trip a malfunction is detected.
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±503