Diagnostic Procedure

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.

With CONSULT-II 

1. Perform "POWER BALANCE" in "ACTIVE TEST" mode with CONSULT-II.
2. Make sure that all circuits do not produce a momentary engine speed drop.

OK or NG 

1. OK: INSPECTION END. 
2. NG: GO TO  4.

Fig 1: Identifying Display - Active Test

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Without CONSULT-II 

1. Let engine idle.
2. Raid the voltage signal between ECM terminal 1 and ground with an oscilloscope.
3. Verify that the oscilloscope screen shows the signal wave as shown below.
   Fig 2: Identifying Oscilloscope Graph

   Courtesy of NISSAN MOTOR CO., U.S.A.
   Fig 3: Identifying Voltage Signal Between ECM Terminal 1

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OK or NG 

1. OK: INSPECTION END. 
2. NG: GO TO 4.

1. Turn ignition switch OFF.
2. Disconnect ignition coil harness connector.
3. Turn ignition switch ON.
   Fig 4: Disconnecting Ignition Coil Harness Connector

   Courtesy of NISSAN MOTOR CO., U.S.A.
4. Check voltage between terminal 7 and ground with CONSULT-II or tester.
   1. Voltage: Battery voltage 

OK or NG 

1. OK: GO TO  6.
2. NG: GO TO 5.

Fig 5: Checking Voltage Between Terminal 7 And Ground

Courtesy of NISSAN MOTOR CO., U.S.A.

Check the following.

• Harness connectors E43, M65
• Harness connectors M59, F27
• Harness for open or short between ignition coil and ignition switch
  1. Repair harness or connectors.

1. Turn ignition switch OFF.
2. Disconnect power transistor harness connector.
3. Check harness continuity between power transistor terminal 2 and engine ground. Refer to Wiring Diagram.
   1. Continuity should exist. 
4. Also check harness for short to power.

OK or NG 

1. OK: GO TO 7.
2. NG: Repair open circuit or short to power in harness or connectors.

1. Strip tape covering resistor.
2. Disconnect resistor harness connector.
3. Check harness continuity between ignition coil terminal 8 and resistor terminal 1, resistor terminal 2 and ECM terminal 2. Refer to Wiring Diagram.
   1. Continuity should exist. 
4. Also check for short to ground and short to power.

OK or NG 

1. OK: GO TO 8.
2. NG: Repair open circuit or short to ground or short to power in harness or connectors.

Check resistance between resistor terminals 1 and 2.

1. Resistance: Approximately 2.2Ω [at 25°C (77°F] 

OK or NG 

1. OK: GO TO 9.
2. NG: Replace resistor.

Fig 6: Check Resistance Between Resistor Terminals 1 And 2

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1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 1 and power transistor 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 10.
2. NG: Repair open circuit or short to ground or short to power in harness or connectors.

1. Disconnect ignition coil harness connector.
2. Check resistance as shown in the figure.
   Fig 7: Disconnect Ignition Coil Harness Connector

   Courtesy of NISSAN MOTOR CO., U.S.A.
   Fig 8: Terminal Resistance Table

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   For checking secondary coil, remove distributor cap and measure resistance between coil tower metal tip 9 and terminal 7.

OK or NG 

1. OK: GO TO 11.
2. NG: Replace distributor assembly.

Fig 9: Measure Resistance Between Coil Tower Metal Tip 9 And Terminal 7

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1. Disconnect camshaft position sensor & power transistor harness connector and ignition coil harness connector.
2. Check power transistor resistance between terminals 2 and 8.
   Fig 10: Check Power Transistor Resistance Between Terminals 2 And 8

   Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG 

1. OK: GO TO 12.
2. NG: Replace distributor assembly.

Fig 11: Terminal Resistance Table

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Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .

1. INSPECTION END.