Page 1271 of 2898

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-547
Page 1272 of 2898
Wiring DiagramNJEC1784SEDAN MODELS AND HATCHBACK MODELS WITH ECM IN ENGINE COMPARTMENTNJEC1784S01
HEC964
IGNITION SIGNALQG
Wiring Diagram
EC-548
Page 1275 of 2898
Diagnostic ProcedureNJEC0579
1 CHECK ENGINE START
Turn ignition switch ªOFFº, and restart engine.
Is engine running?
YesorNo
Yes (With CONSULT-II)©GO TO 2.
Yes (Without CONSULT-
II)©GO TO 12.
No©GO TO 3.
2 SEARCH FOR MALFUNCTIONING CIRCUIT
With CONSULT-II
1. Perform ªPOWER BALANCEº in ªACTIVE TESTº mode with CONSULT-II.
2. Search for circuit which does not produce a momentary engine speed drop.
SEF190Y
©GO TO 12.
3 CHECK IGNITION COIL POWER SUPPLY CIRCUIT-I
1. Turn ignition switch ON.
2. Check voltage between ECM terminals 110, 112 and ground with CONSULT-II or tester.
SEF366X
OK or NG
OK©GO TO 4.
NG©GO TO TROUBLE DIAGNOSIS FOR POWER SUPPLY, EC-178.
IGNITION SIGNALQG
Diagnostic Procedure
EC-551
Page 1276 of 2898
4 CHECK IGNITION COIL POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect condenser harness connector.
JEF121Y
3. Turn ignition switch ON.
4. Check voltage between condenser terminal 1 and ground with CONSULT-II or tester.
SEF367X
OK or NG
OK©GO TO 10.
NG©GO TO 5.
5 CHECK IGNITION COIL POWER SUPPLY CIRCUIT-III
1. Turn ignition switch OFF.
2. Disconnect ECM relay. (For ECM relay location, refer to ªEngine Control Component Parts Locationº.)
3. Check harness continuity between ECM relay terminal 7 and condenser terminal 1. Refer to Wiring Diagram.
Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 7.
NG©GO TO 6.
6 DETECT MALFUNCTIONING PART
Check the harness for open or short between ECM relay and condenser.
©Repair open circuit or short to ground or short to power in harness or connectors.
IGNITION SIGNALQG
Diagnostic Procedure (Cont'd)
EC-552
Page 1277 of 2898

7 CHECK IGNITION COIL POWER SUPPLY CIRCUIT-IV
Check voltage between ECM relay terminal 6 and ground with CONSULT-II or tester.
SEF368X
OK or NG
OK©GO TO 9.
NG©GO TO 8.
8 DETECT MALFUNCTIONING PART
Check the following.
+15A fuse
+Harness connectors E75, F36 (If so equipped)
+Harness for open and short between ECM relay and fuse
©Repair or replace harness or connectors.
9 CHECK ECM RELAY
Refer to ªComponent Inspectionº, EC-555.
OK or NG
OK©GO TO 17.
NG©Replace ECM relay.
10 CHECK CONDENSER GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check harness continuity between condenser terminal 2 and engine ground. Refer to Wiring Diagram.
Continuity should exist.
3. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 11.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
11 CHECK CONDENSER
Refer to ªComponent Inspectionº, EC-555.
OK or NG
OK©GO TO 12.
NG©Replace condenser.
IGNITION SIGNALQG
Diagnostic Procedure (Cont'd)
EC-553
Page 1278 of 2898
12 CHECK IGNITION COIL POWER SUPPLY CIRCUIT-V
1. Turn ignition switch OFF.
2. Reconnect harness connectors disconnected.
3. Disconnect ignition coil harness connector.
JEF119Y
4. Turn ignition switch ON.
5. Check voltage between ignition coil terminal 1 and ground with CONSULT-II or tester.
SEF122Y
OK or NG
OK©GO TO 14.
NG©GO TO 13.
13 DETECT MALFUNCTIONING PART
Check the following.
+Harness connector E75, F36 (If so equipped)
+Harness for open or short between ignition coil and ECM relay terminal 7
©Repair or replace harness or connectors.
14 CHECK IGNITION COIL GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check harness continuity between ignition coil terminal 2 and engine ground. Refer to Wiring Diagram.
Continuity should exist.
3. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 15.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
IGNITION SIGNALQG
Diagnostic Procedure (Cont'd)
EC-554
Page 1285 of 2898

System DescriptionNJEC0444
Sensor Input Signal to ECMECM func-
tionActuator
Crankshaft position sensor (POS) Engine speed
Fuel pump
controlFuel pump relay Camshaft position sensor (PHASE) Engine speed and cylinder number
Ignition switch Ignition signal and start signal
The ECM activates the fuel pump for several seconds after the ignition switch is turned on to improve engine
startability. If the ECM receives a 180É signal from the camshaft position sensor, it knows that the engine is
rotating, and causes the pump to perform. If the 180É signal is not received when the ignition switch is on, the
engine stalls. The ECM stops pump operation and prevents battery discharging, thereby improving safety. The
ECM does not directly drive the fuel pump. It controls the ON/OFF fuel pump relay, which in turn controls the
fuel pump.
Condition Fuel pump operation
Ignition switch is turned to ON. Operates for 1 second
Engine running and cranking Operates
When engine is stopped (Signal is not sent from crankshaft position sensor
and camshaft position sensor.)Stops in 1.5 seconds
Except as shown aboveStops
SEF605X
Component DescriptionNJEC0501A turbine type design fuel pump is used in the fuel tank.
CONSULT-II Reference Value in Data Monitor
Mode
NJEC0445
MONITOR ITEM CONDITION SPECIFICATION
FUEL PUMP RLY+Ignition switch is turned to ON (Operates for 1 second)
+Engine running and cranking
+When engine is stopped (stops in 1.5 seconds)ON
+Except as shown above OFF
FUEL PUMPQG
System Description
EC-561
Page 1286 of 2898
ECM Terminals and Reference Value=NJEC0446Specification 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)
21 B/P Fuel pump relay[Ignition switch ªONº]
+For 1 second after turning ignition switch ªONº
[Engine is running]0-1V
[Ignition switch ªONº]
+More than 1 second after turning ignition switch
ªONºBATTERY VOLTAGE
(11 - 14V)
FUEL PUMPQG
ECM Terminals and Reference Value
EC-562