Diagnosis Procedure
- CHECK ENGINE START
Turn ignition switch OFF and restart engine.
Is engine running?
Yes or No
Yes (With CONSULT-III): GO TO 2.
Yes (Without CONSULT-III): GO TO 3.
No: GO TO 4.
- CHECK OVERALL FUNCTION
With CONSULT-III
- Perform "POWER BALANCE" in "ACTIVE TEST" mode with CONSULT-III.
- Make sure that each circuit produces a momentary engine speed drop.
OK or NG
OK: INSPECTION END
NG: GO TO 10.
- CHECK OVERALL FUNCTION
Without CONSULT-III
- Let engine idle.
- Read the voltage signal between ECM terminals 11, 12, 15, 16, 19, 20 and ground with an oscilloscope.
- Verify that the oscilloscope screen shows the signal wave as shown below.NOTE: The pulse cycle changes depending on RPM at idle.
Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG
OK: INSPECTION END
NG: GO TO 10.
- CHECK IGNITION COIL POWER SUPPLY CIRCUIT-I
- Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
- Check voltage between ECM terminals 125 and ground with CONSULT-III or tester.
Voltage: Battery voltage
OK or NG
OK: GO TO 5.
NG: Go to POWER SUPPLY AND GROUND CIRCUIT .
- CHECK IGNITION COIL POWER SUPPLY CIRCUIT-II
- Turn ignition switch OFF.
- Disconnect condenser harness connector.
- Turn ignition switch ON.
- Check voltage between condenser terminal 1 and ground with CONSULT-III or tester.
Voltage: Battery voltage
OK or NG
OK: GO TO 8.
NG: GO TO 6.
- CHECK IGNITION COIL POWER SUPPLY CIRCUIT-III
- Turn ignition switch OFF.
- Disconnect IPDM E/R harness connector E7.
- Check harness continuity between IPDM E/R terminal 17 and condenser terminal 1.
Refer to WIRING DIAGRAM .
Continuity should exist .
- Also check harness for short to ground and short to power.
OK or NG
OK: GO TO 14.
NG: GO TO 7.
- DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors E12, F3
- Harness for open or short between IPDM E/R and condenser
Repair open circuit or short to ground or short to power in harness or connectors.
- CHECK CONDENSER GROUND CIRCUIT FOR OPEN AND SHORT
- Turn ignition switch OFF.
- Check harness continuity between condenser terminal 2 and ground.
Refer to WIRING DIAGRAM .
Continuity should exist .
- Also check harness for short to power.
OK or NG
OK: GO TO 9.
NG: Repair open circuit or short to power in harness or connectors.
- CHECK CONDENSER
Refer to "COMPONENT INSPECTION ".
OK or NG
OK: GO TO 10.
NG: Replace condenser.
- CHECK IGNITION COIL POWER SUPPLY CIRCUIT-IV
- Turn ignition switch OFF.
- Reconnect all harness connectors disconnected.
- Disconnect ignition coil harness connector.
- Turn ignition switch ON.
- Check voltage between ignition coil terminal 3 and ground with CONSULT-III or tester.
Voltage: Battery voltage
OK or NG
OK: GO TO 11.
NG: Repair open circuit or short to ground or short to power in harness or connectors.
- CHECK IGNITION COIL GROUND CIRCUIT FOR OPEN AND SHORT
- Turn ignition switch OFF.
- Check harness continuity between ignition coil terminal 2 and ground.
Refer to WIRING DIAGRAM .
Continuity should exist .
- Also check harness for short to power.
OK or NG
OK: GO TO 12.
NG: Repair open circuit or short to power in harness or connectors.
- CHECK IGNITION COIL OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
- Disconnect ECM harness connector.
- Check harness continuity between ECM terminals 11, 12, 15, 16, 19, 20 and ignition coil terminal 1.
Refer to WIRING DIAGRAM .
Continuity should exist .
- Also check harness for short to ground and short to power.
OK or NG
OK: GO TO 13.
NG: Repair open circuit or short to ground or short to power in harness or connectors.
- CHECK IGNITION COIL WITH POWER TRANSISTOR
Refer to "COMPONENT INSPECTION ".
OK or NG
OK: GO TO 14.
NG: Replace malfunctioning ignition coil with power transistor.
- CHECK INTERMITTENT INCIDENT
Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .
OK or NG
OK: Replace IPDM E/R.
NG: Repair open circuit or short to ground or short to power in harness connectors.