1995 TOYOTA SUPRA fuel

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
(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

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
 
 6 IGF signals detected in 6 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
 
 
 
 
 
 
Volume of air flowing is measured by turbo pressure
Sensor to determine injection volume and ignition
Timing
 
 
 
 
 
 
Returned to normal condition
 
 34
 
 Fuel cut
 
 Returned to normal condition
  Turbo  
  
Turbo
Pressure Fuel cut Returned to normal condition
 35 Sensor  
 
 
35
 
 
BARO
Sensor 
 
Atmospheric pressure is fixed at
101.3 kPa (760 mmHg, 29.92 inVHg) 
 Returned to normal condition
 
 
 
 
41
 
 
 
 
VTA1 is fixed at closed throttle position
 
 
 
 
The following must each be repeated at
least 2 times consecutively:

0.1 V
VTA1
0.95 V

IDL: ON
 
 
 
47
 
 
 
VTA2 is fixed at wide open throttle
Position 
 
 
The following must be repeated at least 2
times consecutively

0.1 V
VTA2
0.95 V
 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±504
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

(See page
IG±26)
Check fuel pressure.
Proceed to page EG±264 and continue to
troubleshoot.
(1) Be sure that there is enough fuel in the tank.
(2) Turn ignition switch ON.
(3) Using SST, connect terminals FP and +B of
data link connector 1.
SST 09843±18020
Check that there is pressure in the hose from the fuel
filter.
If there is fuel pressure, you will hear the sound of fuel
flowing.
Never make a mistake with the terminal con-
nection position as this will cause a malfunc-
tion.
Check for spark.
Proceed to page IG±21 and continue to trou-
bleshoot.
Proceed to matrix chart of problem symptoms
on page EG±514.
(1) Remove ignition coil (See page IG±26)
(2) Remove spark plug.
(3) Install the spark plug to the ignition coil, and connect
the ignition coil connector.
(4) Ground the spark plug.
Check if spark occurs while 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±508± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

Suspect area
See page
Symptom
Engine does not crank
No initial combustion
No complete combustion
Engine cranks normally
Cold engine
Hot engine
Incorrect first idle
High engine idle speed
Low engine idle speed
Rough idling
Hunting
Hesitation/Poor acceleration
Muffler explosion (after fire)
Surging
Soon after starting
After accelerator pedal depressed
After accelerator pedal released
During A/C operation
When shifting N to D
Does not
start
Difficult to
start
Poor Idling
Engine Stall
Poor
Driveability
Back up power source circuitECM power source circuitPark/neutral position switch circuitSwitch condition signal circuitEGR systemStarter signal circuitMass air flow meter circuitInjector circuitIAC valve circuitFuel pump control circuitA/C signal circuit (Compressor circuit)Turbo control circuitVSV circuit for fuel Pressure ControlCompressionSpark plugIgnition signal circuit (Spark test)Starter and Starter relayIgnition coilEngine control module (ECM)Theft deterrent ECUA/T faulty
EG±544EG±559EG±564EG±571EG±574EG±576EG±581EG±583EG±586EG±568EG±595EG±589AC±62ST±3
,
12
IG±21IG±23IG±22EG±9AT2±101BE±123IN±35
MATRIX CHART OF PROBLEM SYMPTOMS
When the malfunction code is not confirmed in the diagnostic trouble code check and the problem still can not
be confirmed in the basic inspection, proceed to this matrix chart and troubleshoot according to the numbered
order given below. EG±514
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

DTC 14 Ignition Signal Circuit
CIRCUIT DESCRIPTION
The ECM determines the ignition timing, turns on Tr1 at a predetermined angle (°CA) before the desired ignition
timing and outputs an ignition signal (IGT) º1º to the igniter.
Since the width of the IGT signal is constant, the dwell angle control circuit in the igniter determines the time
the control circuit starts primary current flow to the ignition coil based on the engine rpm and ignition timing one
revolution ago, that is, the time the Tr
2 turns on.
When it reaches the ignition timing, the ECM turns Tr
1 off and outputs the IGT signal ºOº.
This turns Tr
2 off, interrupting the primary current flow and generating a high voltage in the secondary coil which
causes the spark plug to spark. Also, by the counter electromotive force generated when the primary current
is interrupted, the igniter sends an ignition confirmation signal (IGF) to the ECM.
The ECM stops fuel injection as a fail safe function when the IGF signal is not input to the ECM.
 DTC No. Diagnostic Trouble Code Detecting Condition Trouble Area 
 
 
 
14
 
 
 
 
No IGF signal to ECM for 4 ~ 7 consecutive
IGT signals with engine speed less than
3,000 rpm
 
 
 
 

Open or short in IGF circuit from igniter to
ECM

Igniter

ECM
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±519