1995 TOYOTA SUPRA fuel

DTC
No.Number of
MIL BlinksCircuitDiagnostic Trouble Code Detecting Condition
Engine Coolant
Temp. Sensor
Circuit
Intake Air Temp.
Sensor Signal
Air±Fuel Ratio
Lean Malfunction
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*3) oxygen sensor voltage is 0.45 V or less (lean)
for 90 sec. under conditions (a) and (b):
(2 trip detection logic)*
4
(a) Engine speed: 1,500 rpm or more
(b) Engine coolant temp.: 70°C (158°F) or more
(2)*3Difference of air±fuel ratio feedback compensation value
between front (no.1 ~ 3 cylinders) and rear (No.4 ~ 6
cylinders) is more tan 15 percentage for 20 sec. or more
under conditions (a) and (b):
(2 trip detection logic)*
4
(a) Engine speed: 2,000 rpm or more
(b) Engine coolant temp.: Between 60°C (140°F) and
95°C (203°F)
(3)*3Engine speed varies by more than 15 rpm over the preceding
crank angle period during a period o 20 sec. or more under
conditions (a) and (b):
(2 trip detection logic)*
4
(a) Engine speed: Idling
(b) Engine coolant temp.: Between 60°C (140°F) and
95°C (203°F)
*3, 4: See page EG±396 397. EG±390
± ENGINE2JZ±GE 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 engine coolant temp. sensor circuit

Engine coolant temp. sensor

ECM
 
 
 
 
ON
 
 
 
 
ON
 
 
 
 

 
 
 
 
EG±424
 
 
 
 
 

Open or short in intake air temp. sensor circuit

Intake air temp. sensor

ECM
 
 
 
 
 
ON
 
 
 
 
 
ON
 
 
 
 
 

 
 
 
 
 
EG±426
 
 
 
 
 

Open or short in (main heated*3) oxygen sensor circuit

(Main heated*3) oxygen sensor

Ignition system

ECM
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 


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)

Volume air flow meter (air intake)

ECM
 
 
 
 
 
 

ON
 
 
 
 
 
 

ON
 
 
 
 
 
 


 
 
 
 
 
 

EG±428
 
 
 
 
 
 
 

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)

Volume air flow meter (air intake)

ECM
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
*1, 2, 3: See page EG±396.
± ENGINE2JZ±GE ENGINE TROUBLESHOOTINGEG±391

DTC
No.Number of
MIL BlinksCircuitDiagnostic Trouble Code Detecting Condition
Air±Fuel Ratio
Rich Malfunction
(1) Difference of air±fuel ratio feedback compensation value
between front (No.1 ~ 3 cylinders) and rear (No.4 ~ 6
cylinders) is more than 15 percentage for 20 sec. or
more under conditions(a) and (b):
(2 trip detection logic)*
4
(a) Engine speed: 2,000 rpm or more
(b) Engine coolant temp.: Between 60°C (140°F) and
95°C (203°F)
(2) Engine speed varies by more than 15 rpm over the preceding
crank angle period during a period o 20 sec. or more under
conditions (a) and (b):
(2 trip detection logic)*
4
(a) Engine speed: 2,000 rpm or more
(b) Engine coolant temp.: Between 60°C (140°F) and
95°C (203°F)
(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
oxygen sensor signal is 0.45 V or less under conditions (a) ~ (c):
(2 trip detection logic)*
4
(a) Engine coolant temp.: 80°C (176°F) or more
(b) Engine speed: 1,500 rpm or more
(c) Accel. pedal: Fully depressed for 2 sec. or more
(1)*3Open or short in heater circuit of main heated oxygen
sensor (Rr) for 0.5 sec. or more|
(2) (Main heated*3) oxygen sensor (Rr) signal voltage is
reduced to between 0.35 V and 0.70 V for 90 sec.
under conditions (a) ~ (d)
(2 trip detection logic)*
4
(b) 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*3) oxygen sensor (Rr) signal voltage:
Alternating above and below 0.45 V
Sub Heated
Oxygen Sensor
Signal
(Main heated*3)
Oxygen Sensor
Signal (Rr)
*3, 4: See page EG±396, 397 EG±392
± ENGINE2JZ±GE 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)

Volume air flow meter (air intake)

ECM
 
 
 
 
 
 
 ON
 
 
 
 
 
 
 ON
 
 
 
 
 
 
 
 
 
 
 
 
 
 EG±428
 
 
 
 
 
 

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)

Volume air flow meter (air intake)

ECM
 
 
 
 
 
 
ON
 
 
 
 
 
 
ON
 
 
 
 
 
 

 
 
 
 
 
 
EG 428
 
 
 

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±434
 
 
 

Open or short in heater circuit of main heated oxygen sensor (Rr)

Main heated oxygen sensor (Rr) heater

ECM
 
 
 
ON
 
 
 
N.A.
 
 
 
 
 
 
 
 
 
 
 
 
 

(Main heated*3) oxygen sensor (Rr) circuit

(Main heated*3) oxygen sensor (Rr)
 
 
 
 
 
 
 
ON
 
 
 
 
 
 
 
ON
 
 
 
 
 
 
 

 
 
 
 
 
 
 
EG±419
*1, 2, 3: See page EG±396.
± ENGINE2JZ±GE ENGINE TROUBLESHOOTINGEG±393

DTC
No.Number of
MIL BlinksCircuitDiagnostic Trouble Code Detecting Condition
EGR System
Malfunction
Fuel Pump
Control Signal
Switch Condition
Signal
(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 ªRº, ªDº, ª2º, or ªLº position)
(3) A/C switch ON
(3) Open or short in diagnostic signal line (DI) of fuel pump
ECU with engine speed 1,000 rpm or less
(2 trip detection logic)*
4
(2) Open in input circuit of fuel pump ECU (FPC) with engine
speed 1,000 rpm or less
(2 trip detection logic)*
4
(1) Open or short in fuel pump circuit for 1 sec. or more with
engine speed 1,000 rpm or less
(2 trip detection logic)*
4
EGR gas temp. is 70°C (158°F) or less for 1 Ð 4 min. under
conditions (a) and (b):
(2 trip detection logic)*
4
(a) Engine Coolant temp.: 63°C (145°F) or more
(b) EGR operation possible (Example A/T in 3rd speed (5th for
M/T),
A/C ON, 96 km/h (60 mph), Flat road)
*1: ºONº displayed in the diagnostic mode column indicates that the Malfunction Indicator Lamp is lit up when
a malfunction is detected. ºOFFº indicates that the ºCHECKº does not light up during malfunction
diagnosis, even if a malfunction is detected. ºN.A.º indicates that the item is not included in malfunction
diagnosis.
*2: º
º 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.
*3: Only for California specification vehicles. EG±396
± ENGINE2JZ±GE ENGINE TROUBLESHOOTING

 
 
 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±453
 
 
 
 
 
 
 
 
 
 
 
 
 

Open or short in fuel pump ECU circuit

Fuel pump ECU

Fuel pump

ECM power source circuit

ECM
 
 
 
 
 
 
 
 
 
 
 
 
 
OFF
 
 
 
 
 
 
 
 
 
 
 
 
 
ON
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
EG±457
 
 
 
 
 
 

A/C switch circuit

Throttle position sensor IDL circuit

Park/neutral position switch circuit

Accelerator pedal and cable

ECM
 
 
 
 
 
 
N.A.
 
 
 
 
 
 
OFF
 
 
 
 
 
 
X
 
 
 
 
 
 
EG±460
*4: 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±GE ENGINE TROUBLESHOOTINGEG±397

FAIL±SAFE CHART
If any of the following codes is detected, the ECM enters fail±safe mode.
 DTC No. Fail±Safe Operation Fail±Safe Deactivation Conditions
 14 Fuel cut 1 IGF detected in 3 consecutive ignitions
 16 Torque control prohibited Returned to normal condition
 22 THW is fixed at 80°C (176°F) Returned to normal condition 24 THA is fixed at 20°C (68°F) Returned to normal condition 
 
 
 
 
 
31
 
 
 
 
 
 

Ignition timing fixed at 10°BTDC

Injection time fixed:
(Starting....9 msec.
(IDL ON....3.6 msec.
(IDL OFF....6.7 msec.
 
 
 
 
 
 
KS input 15 times/sec. or more
 
 35
 
 
Atmospheric pressure is fixed at 101.3 kPa
(760 mmHg, 29.92 in.Hg) 
 Returned to normal condition
 
 
 
 

41
 
 
 
 

VTA1 is fixed at 0°
 
 
 
 

The following must each be repeated at least 2
Times consecutively:

0.25 V
VTA
0.95 V

IDL: ON 
 52
 
 Max. timing retardation
 
 IG switch OFF
 53 Max. timing retardation Returned to normal condition
 55 Max. timing retardation IG switch OFF
Back±Up Function
If there is trouble with the program in the ECM and the ignition signals (IGT) are not output from the microcomput-
er, the ECM controls fuel injection and ignition timing at predetermined levels as a back±up function to make
it possible to continue to operate the vehicle.
Furthermore, the injection duration is calculated from the starting signal (STA) and the throttle position signal
(IDL). Also, the ignition timing is fixed at the initial ignition timing, 10°BTDC, without relation to the engine speed.
HINT: if the engine is controlled by the back±up function, the malfunction indicator lamp lights up to warn the
driver of the malfunction but the diagnostic trouble code is not output. EG±398
± ENGINE2JZ±GE ENGINE TROUBLESHOOTING

EG±193
IG±4
EG±408.
(1) Be sure that there is enough fuel in the tank.
(2) Turn ignitiion switch ON.
(3) Using SST, connect terminals FP and +B of data
link connector 1.
SST 09834±18020
Check that there is pressure in the hose from the
fuel filter.
If there is fule pressure, you will hear the sound of
fuel flowing.
Never make a mistake with the terminal connection
position as this will cause a malfunction.
Check fuel pressure.
Check for spark.
Proceed to page EG±193 and continue to trou-
bleshoot.
Proceed to page IG±4 and continue to trouble-
shoot.
Proceed to matrix chart of problem symptoms on
page EG±408.
Disconnect the high±tension cord from the distributor and hold the end about 12.5 mm (1/2º) from the ground.
See if spark occurs while the engine is being cranked.
To prevent excess fuel being injected from the injectors during this test, don't crank the engine for more than
1 Ð 2 seconds at a time.
EG±402± ENGINE2JZ±GE ENGINE TROUBLESHOOTING