Page 420 of 2493

Symptom Matrix ChartNJEC0041SYSTEM Ð ENGINE CONTROL SYSTEMNJEC0041S01
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Fuel Fuel pump circuit11232 22 3 2EC-464
Fuel pressure regulator sys-
tem334444444 4EC-39
Injector circuit11232 22 2EC-447
Evaporative emission sys-
tem334444444 4EC-33
Air Positive crankcase ventila-
tion system334444444 41EC-37
Incorrect idle speed adjust-
ment3 3 1 1 1 1 1 EC-41
IACV-AAC valve circuit112332222 2 2EC-313
Ignition Incorrect ignition timing
adjustment33111 11 1EC-41
Ignition circuit11222 22 2EC-451
EGR EGR volume control valve
circuit2233 3EC-293
EGR system212333223 3EC-285,
293, 353
Main power supply and ground circuit22333 33 23 2EC-145
Air conditioner circuit223333333 3 2HAsection
1 - 6: The numbers refer to the order of inspection.
(continued on next page)
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONQG
Symptom Matrix Chart
EC-124
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5 CHECK POWER SUPPLY-II
1. Disconnect ECM relay. (For ECM relay location, refer to ªEngine Control Compartment Parts Locationº.)
2. Check voltage between ECM relay terminals 1, 6 and ground with CONSULT-II or tester.
SEF101Y
OK or NG
OK©GO TO 7.
NG©GO TO 6.
6 DETECT MALFUNCTIONING PART
Check the following.
+15A fuse and 10A fuse
+Harness for open or short between ECM relay and battery
©Repair open circuit or short to ground or short to power in harness or connectors.
7 CHECK OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 31 and ECM relay terminal 2.
Continuity should exist.
2. Also check harness for short to ground and short to power.
OK or NG
OK©Go to ªIGNITION SIGNALº, EC-451.
NG©GO TO 8.
8 DETECT MALFUNCTIONING PART
Check the harness for open or short between ECM relay and ECM.
©Repair open circuit or short to ground or short to power in harness or connectors.
TROUBLE DIAGNOSIS FOR POWER SUPPLYQG
Main Power Supply and Ground Circuit (Cont'd)
EC-148
Page 561 of 2493

6 CHECK IGNITION SPARK
1. Turn Ignition switch ªOFFº.
2. Disconnect ignition coil assembly from rocker cover.
3. Connect a known good spark plug to the ignition coil assembly.
4. Place end of spark plug against a suitable ground and crank engine.
5. Check for spark.
SEF575Q
OK or NG
OK©GO TO 7.
NG©Check ignition coil, power transistor and their circuits. Refer to EC-451.
7 CHECK SPARK PLUGS
Remove the spark plugs and check for fouling, etc.
SEF156I
OK or NG
OK©GO TO 8.
NG©Repair or replace spark plug(s) with standard type one(s). For spark plug type, refer to
EM-18, ªChecking and changingº.
8 CHECK COMPRESSION PRESSURE
Refer to EM section.
+Check compression pressure.
Standard:
1,324 kPa (13.24 bar, 13.5 kg/cm
2, 192 psi)/350 rpm
Minimum:
1,128 kPa (11.28 bar, 11.5 kg/cm
2, 164 psi)/350 rpm
Difference between each cylinder:
98 kPa (0.98 bar, 1.0 kg/cm
2, 14 psi)/350 rpm
OK or NG
OK©GO TO 9.
NG©Check pistons, piston rings, valves, valve seats and cylinder head gaskets.
DTC P0300 - P0304 NO.4-1CYLINDER MISFIRE, MULTIPLE CYLINDER
MISFIRE
QG
Diagnostic Procedure (Cont'd)
EC-265
Page 598 of 2493

5 CHECK INJECTORS
1. Refer to Wiring Diagram for Injectors, EC-447.
2. Stop engine and then turn ignition switch ªONº.
3. Check voltage between ECM terminals 101, 103, 105 and 107 and ground with CONSULT-II or tester.
SEF075X
Battery voltage should exist.
OK or NG
OK©GO TO 6.
NG©Perform ªDiagnostic Procedureº INJECTOR, EC-448.
6 CHECK IGNITION SPARK
1. Disconnect ignition coil assembly from rocker cover.
2. Connect a known good spark plug to the ignition coil assembly.
3. Place end of spark plug against a suitable ground and crank engine.
4. Check for spark.
SEF575Q
OK or NG
OK©GO TO 7.
NG©Check ignition coil, power transistor and their circuits. Refer to EC-451.
7 CHECK INJECTOR
1. Turn ignition switch ªOFFº.
2. Remove injector assembly. Refer to EC-39.
Keep fuel hose and all injectors connected to injector gallery.
3. Disconnect camshaft position sensor harness connector.
4. Turn ignition switch ªONº.
Make sure fuel does not drip from injector.
OK or NG
OK (Does not drip)©GO TO 8.
NG (Drips)©Replace the injector(s) from which fuel is dripping.
DTC P0420 THREE WAY CATALYST FUNCTIONQG
Diagnostic Procedure (Cont'd)
EC-302
Page 747 of 2493

Component DescriptionNJEC0542IGNITION COIL AND POWER TRANSISTORNJEC0542S01The ignition signal from the ECM is sent to and amplified by the
power transistor. The power transistor turns on and off the ignition
coil primary circuit. This on-off operation induces the proper high
voltage in the coil secondary circuit.
CONSULT-II Reference Value in Data Monitor
Mode
NJEC0543Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
IGNITION SW+Ignition switch: ON®OFF®ON ON®OFF®ON
ECM Terminals and Reference ValueNJEC0544Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
35
36
37
38L/W
PU
L/R
GY/RIgnition signal (No. 1)
Ignition signal (No. 2)
Ignition signal (No. 3)
Ignition signal (No. 4)[Engine is running]
+Warm-up condition
+Idle speed0 - 0.2V
SEF971W
[Engine is running]
+Engine speed is 2,000 rpm0.2 - 0.4V
SEF972W
IGNITION SIGNALQG
Component Description
EC-451
Page 1358 of 2493
Diagnostic ProcedureNJAT0042
1 CHECK DTC WITH ECM
Perform diagnostic test mode II (self-diagnostic results) for engine control. Check ignition signal circuit condition.
OK or NG
OK (With CONSULT-II)©GO TO 2.
OK (Without CONSULT-
II)©GO TO 3.
NG©Check ignition signal circuit for engine control. Refer to EC-451, ªIGNITION SIGNALº.
2 CHECK INPUT SIGNAL (With CONSULT-II)
With CONSULT-II
1. Start engine.
2. Select ªECU INPUT SIGNALSº in ªDATA MONITORº mode for ªA/Tº with CONSULT-II.
SAT580J
3. Read out the value of ªENGINE SPEEDº.
Check engine speed changes according to throttle position.
SAT645J
OK or NG
OK©GO TO 4.
NG©Check the following items:
+Harness for short or open between TCM and ECM
+Resistor and ignition coil
Refer to EC-451, ªIGNITION SIGNALº.
ENGINE SPEED SIGNALEXCEPT FOR EURO-OBD
Diagnostic Procedure
AT-172
Page 1359 of 2493
3 CHECK INPUT SIGNAL (Without CONSULT-II)
Without CONSULT-II
1. Start engine.
2. Check voltage between TCM terminal 39 and ground.
Voltage (Idle speed):
Refer to EC-489, ªIdle Speed and Ignition Timingº.
SAT424JA
OK or NG
OK©GO TO 4.
NG©Check the following items:
+Harness for short or open between TCM and ECM
+Resistor and ignition coil
Refer to EC-451, ªIGNITION SIGNALº.
4 CHECK DTC
Perform Self-diagnosis Code confirmation procedure, AT-170.
OK or NG
OK©INSPECTION END
NG©1. Perform TCM input/output signal inspection.
2. If NG, recheck TCM pin terminals for damage or loose connection with harness con-
nector.
ENGINE SPEED SIGNALEXCEPT FOR EURO-OBD
Diagnostic Procedure (Cont'd)
AT-173
Page 1386 of 2493
Diagnostic ProcedureNJAT0278
1 CHECK DTC WITH ECM
Perform diagnostic test mode II (self- diagnostic results) for engine control. Check ignition signal circuit condition.
OK or NG
OK (With CONSULT-II)©GO TO 2.
OK (Without CONSULT-
II)©GO TO 3.
NG©Check ignition signal circuit for engine control. Refer to EC-451, ªIGNITION SIGNALº.
2 CHECK INPUT SIGNAL (With CONSULT-II)
With CONSULT-II
1. Start engine.
2. Select ªECU INPUT SIGNALSº in ªDATA MONITORº mode for ªA/Tº with CONSULT-II.
SAT014K
3. Read out the value of ªENGINE SPEEDº.
Check engine speed changes according to throttle position.
SAT645J
OK or NG
OK©GO TO 4.
NG©Check the following items:
+Harness for short or open between TCM and ECM
+Resistor and ignition coil
Refer to EC-451, ªIGNITION SIGNALº.
DTC P0725 ENGINE SPEED SIGNALEURO-OBD
Diagnostic Procedure
AT-200