Page 1910 of 2543
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
Page 1911 of 2543
PARTS LOCATION
± ENGINE2JZ±GE ENGINE TROUBLESHOOTINGEG±403
Page 1912 of 2543
STANDARD VALUE OF ECM TERMINALS
Connectors of the engine control module are waterproof and are
the bolt type.
For waterproof type connectors, in order to measure the voltage
of ECM terminals and the resistance of connected parts, connect
the inspection sub wire harness between the ECM and vehicle
wire harness, then do the inspection.
The inspection method of inserting a tester probe from the other
side of connector significantly reduces the waterproof perfor-
mance.
Disconnect the connector by fully loosening the bolt.
PREPARATION
1. Turn the ignition switch OFF.
2. Turn up the passenger side floor carpet.
(See page EG±253)
3. Remove the ECM protector.
4. Disconnect the connector from the ECM.
After completely loosening the bolt, the 2 parts of the connec-
tor can be separated.
NOTICE:
wDo not pull the wire harness when disconnecting the con-
nector.
wWhen disconnecting the connector, the ECM's back±up
power source is cut off, so the malfunction codes, etc. re-
corded in the ECM memory are cancelled.
wNever insert a tester probe or male terminal used for in-
spection purposes into the female terminal of the vehicle
wire harness. Otherwise, the female terminal may be wid-
ened, which can result in faulty connection.
5. Connect SST (check harness ºAº) between the ECM and
connector of the vehicle wire harness.
SST 09990±01000
HINT: The arrangement of the check connector terminals are
the same as those of the ECM.
See page EG±405.
6. Disconnect the SST.
SST 09990±01000
7. Reconnect the connector to the ECM.
(a) Match the male connector correctly with the female
connector, then press them together.
(b) Tighten the bolt.
Make sure the connector is completely connected by
tightening the bolt until there is a clearance of less than
1 mm (0.04 in.) between the bottom of the male connec-
tor and the end of the female connector.
8. Install the ECM protector and floor carpet. EG±404
± ENGINE2JZ±GE ENGINE TROUBLESHOOTING
Page 1913 of 2543
(See page EG±439)
(See page EG±472)
(See page EG±415)
(See page EG±415)
(See page EG±410)
(See page EG±410)
Symbols (Terminals No.)STD Voltage (V)Condition
Always
IG switch ON
IG switch ON and apply vacuum to the
throttle opener Throttle valve fully closed
IG switch ON
IG switch ON
Throttle valve fully opened
IG switch ON
Throttle valve fully closed
IG switch ON
Throttle valve fully opened
IdlingPulse generation
Idling, Intake air temp. 0°C (32°F) to 80°C
(176°F)
Idling, Engine coolant temp. 60°C (140°F) to
120°C (248°F)
Cranking
IG switch ON
Idling
Idling
IG switch ON
IG switch ON
IG switch ON
Idling
Idling
Idling
Idling
Idling
Pulse generation
Pulse generation
Pulse generation
Pulse generation
Pulse generation
Pulse generation
STANDARD VALUE OF ECM TERMINALS
± ENGINE2JZ±GE ENGINE TROUBLESHOOTINGEG±405
Page 1914 of 2543
Symbols (Terminals No.) STD Voltage (V) Condition
ACIS (B39)±E01 (B80) 9 ~ 14 IG switch ON
EVAP (B74)±E01 (B80) 9 ~ 14 IG switch ON
EGR (B75) E01 (B80)
Below 2.0
Idling
EGR (B75)±E01 (B80) 9 ~ 14 Engine speed at 3,500 rpm
ISC1 (B35), ISC2 (B34)
±E01 (B80)
ISC3 (B33), ISC4 (B32)
Pulse generation
(See page EG±475)
Idling, when A/C switch ON or OFF
VF1 (B29), VF2 (B28)±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)
OX3 (A30)*
Pulse generation
(See page EG±423)
Maintain engine speed at 2,500 rpm for 2
minutes after warming up
HT1 (B73)*, HT2 (B72)*±E01 (B80)
Below 3.0
Idling
HT1 (B73) , HT2 (B72) E01 (B80)
HT3 (A36)* 9 ~ 14 IG switch ON
KNK1 (B50), KNK2 (B49)±E1 (B69)
Pulse generation
(See page EG±452)
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±445)
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
W (A6)±E1 (B69) 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
A/C (A34)±E1 (B69) 0 ~ 1.5 A/C switch ON (At idling)
ACMG (A23) E1 (B69)
0 ~ 3.0 A/C switch ON (At idling)
ACMG (A23)±E1 (B69)
9 ~ 14
A/C switch OFF
FPU (B36)*E01 (B80) 9 ~ 14 IG switch ON
FPU (B36)*±E01 (B80) Below 2.0 Restarting at high engine coolant temp.
ELS (A15) E1 (B69)
7.5 ~ 14 Defogger switch and taillight switch ON
ELS (A15)±E1 (B69)
0 ~ 1.5
Defogger switch and taillight switch OFF
*: Only for California specification vehicles EG±406
± ENGINE2JZ±GE ENGINE TROUBLESHOOTING
Page 1915 of 2543
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. 2.0 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 ~ 25 steps
Step increases
Step increases
Approx. 125 steps
ENGINE SPEED RPM kept stable (Comparison with tachometer) No great changes
VA F
Engine idling at normal operating temp.*1
Increase engine speed
Approx. 35 ms
Gradually decreases
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*5 Engine idling at normal operating temp. 2.50 + 1.25 V*3
TARGET A/FR*6 Engine idling at normal operating temp. 2.50 + 1.25 V*3
A/F FB LEFT*5 RPM stable at 2500 rpm with normal operating temp. ON
A/F FB RIGHT*6 RPM stable at 2500 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
O X L*5 RPM stable at 2500 rpm with normal operating temp. RICH LEAN is repeated O X R*6 RPM stable at 2500 rpm with normal operating temp. RICH LEAN is repeated
*1: If the engine coolant temp. sensor circuit is open or shorted, the ECM assumes an engine coolant temp.
value of 80
°C (176°F).
*
2: When feedback control is forbidden, 0 V is displayed.
*
3: A/T only
*
4: Oxygen sensor (Front)
*
5: Oxygen sensor (Rear)
± ENGINE2JZ±GE ENGINE TROUBLESHOOTINGEG±407
Page 1916 of 2543
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±438EG±438EG±453EG±460EG±463EG±465EG±470EG±472EG±475EG±457EG±481AC±62ST±3, 12IG±4IG±5IG±7IG±7EG±9AT2±81BE±123IN±35
See page
Suspect area
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 notstart
Difficult tostart
Poor Idling
Poor
Driveability
Engine Stall
Volume air flow meter circuitECM power source circuitPark/neutral position switch circuitSwitch condition signal circuitEGR systemStarter signal circuitStarter and Starter relayA/C signal circuit (Compressor circuit)VSV circuit for fuel pressure controlFuel pump control circuitIAC valve circuitInjector circuitBack up power source circuitIgnition coilSpark plugIgnition signal circuit (Spark test)CompressionA/T faultyDistributorEngine control module (ECM)Theft deterrent ECU
EG±408± ENGINE2JZ±GE ENGINE TROUBLESHOOTING
Page 1917 of 2543
CIRCUIT INSPECTION
DTC 12 G NE Signal Circuit (No.1)
CIRCUIT DESCRIPTION
The distributor in the Engine Control System contains 3 pick±up coils (G1, G2 and NE).
The G1, G2 signals inform the ECM of the standard crankshaft angle.
The NE signals inform the ECM of the crankshaft angle and the engine speed.
DTC No. Diagnostic Trouble Code Detecting Condition Trouble Area
12
No ºNEº or ºG1º and ºG2º signal to ECM for
2 sec. or more after cranking
Open or short in NE, G circuit
Distributor
Open or short in STA circuit
12
Open in ºGª circuit Open or short in STA circuit
ECM
± ENGINE2JZ±GE ENGINE TROUBLESHOOTINGEG±409
