Diagnostic Procedure

CHECK ENGINE START
Turn ignition switch OFF, and restart engine.

Is engine running?

Yes or No
1. Yes (With CONSULT-II): GO TO 2.
2. Yes (Without CONSULT-II): GO TO 3.
3. No: GO TO 4.
CHECK OVERALL FUNCTION
With CONSULT-II
1. Perform "POWER BALANCE" in "ACTIVE TEST" mode with CONSULT-II.
2. Make sure that each circuit produces a momentary engine speed drop.
OK or NG
1. OK: INSPECTION END
2. NG: GO TO 13.
Fig 1: Display Active Test Mode
Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK OVERALL FUNCTION
Without CONSULT-II
1. Let engine idle.
2. Read the voltage signal between ECM terminals 46, 60, 61, 62, 65, 79, 80, 81 and ground with an oscilloscope.
3. Verify that the oscilloscope screen shows the signal wave as shown below.
  NOTE: The pulse cycle changes depending on rpm at idle.
  
  Fig 2: Checking Voltage Signal Between ECM Terminals 46, 60, 61, 62, 65, 79, 80, 81 And Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  Fig 3: ECM Terminals Signal Wave Form
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG
1. OK: INSPECTION END
2. NG: GO TO 13.
CHECK IGNITION COIL POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
2. Check voltage between ECM terminals 119, 120 and ground with CONSULT-II or tester.
  1. Voltage: Battery voltage
OK or NG
1. OK: GO TO 5.
2. NG: go to "POWER SUPPLY AND GROUND CIRCUIT ".
Fig 4: Checking Voltage Between ECM Terminals 119, 120 And Ground
Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK IGNITION COIL POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect condenser harness connector.
3. Turn ignition switch ON.
  
  Fig 5: Locating Condenser Harness Connector
  Courtesy of NISSAN MOTOR CO., U.S.A.
4. Check voltage between condenser terminal 1 and ground with CONSULT-II or tester.
  1. Voltage: Battery voltage
OK or NG
1. OK: GO TO 11.
2. NG: GO TO 6.
Fig 6: Checking Voltage Between Condenser Terminal 1 And Ground
Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK IGNITION COIL POWER SUPPLY CIRCUIT-III
1. Turn ignition switch OFF.
2. Disconnect ECM relay.
3. Check harness continuity between ECM relay terminal 3 and condenser terminal 1.
  Refer to WIRING DIAGRAM .
  1. Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
1. OK: GO TO 8.
2. NG: GO TO 7.
Fig 7: Locating ECM And Fuel Pump Relay
Courtesy of NISSAN MOTOR CO., U.S.A.
DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors M135, F105
- Fuse block (J/B) No. 2 harness connector M143
- Harness for open or short between ECM relay and condenser
  1. Repair open circuit or short to ground or short to power in harness or connectors.
CHECK IGNITION COIL POWER SUPPLY CIRCUIT-IV
Check voltage between ECM relay terminal 5 and ground with CONSULT-II or tester.
1. Voltage: Battery voltage
OK or NG
1. OK: GO TO 10.
2. NG: GO TO 9.
Fig 8: Checking Voltage Between ECM Relay Terminal 5 And Ground
Courtesy of NISSAN MOTOR CO., U.S.A.
DETECT MALFUNCTIONING PART
Check the following.
- 20A fuse
- Fuse, fusible link and relay block (J/B) harness connector E3
- Fuse block (J/B) No. 2 harness connector E215
- Harness for open and short between ECM relay and fuse
  1. Repair or replace harness or connectors.
CHECK ECM RELAY
Refer to "COMPONENT INSPECTION ".

OK or NG
1. OK: GO TO 18.
2. NG: Replace ECM relay.
CHECK CONDENSER CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect condenser harness connector.
3. Check harness continuity between condenser terminal 2 and ground.
  Refer to WIRING DIAGRAM .
  1. Continuity should exist.
4. Also check harness for short to power.
OK or NG
1. OK: GO TO 12.
2. NG: Repair open circuit or short to power in harness or connectors.
CHECK CONDENSER
Refer to "COMPONENT INSPECTION "

OK or NG
1. OK: GO TO 13.
2. NG: Replace condenser.
CHECK IGNITION COIL POWER SUPPLY CIRCUIT-V
1. Reconnect all harness connectors disconnected.
2. Disconnect ignition coil harness connector.
  
  Fig 9: Locating Ignition Coil Harness Connector
  Courtesy of NISSAN MOTOR CO., U.S.A.
3. Turn ignition switch ON.
4. Check voltage between ignition coil terminal 3 and ground with CONSULT-II or tester.
  1. Voltage: Battery voltage
OK or NG
1. OK: GO TO 15.
2. NG: GO TO 14.
Fig 10: Checking Voltage Between Ignition Coil Terminal 3 And Ground
Courtesy of NISSAN MOTOR CO., U.S.A.
DETECT MALFUNCTIONING PART
Check the harness for open or short between ignition coil and ECM relay.
1. Repair or replace harness or connectors.
CHECK IGNITION COIL GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check harness continuity between ignition coil terminal 2 and ground.
  Refer to WIRING DIAGRAM .
  1. Continuity should exist.
3. Also check harness for short to power.
OK or NG
1. OK: GO TO 16.
2. NG: Repair open circuit or short to power in harness or connectors.
CHECK IGNITION COIL OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminals 46, 60, 61, 62, 65, 79, 80, 81 and ignition coil terminal
  1. Refer to WIRING DIAGRAM .
    1. Continuity should exist.
3. Also check harness for short to ground and short to power.
OK or NG
1. OK: GO TO 17.
2. 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
1. OK: GO TO 18.
2. NG: Replace ignition coil with power transistor.
CHECK INTERMITTENT INCIDENT
Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".
1. INSPECTION END