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Ignition System

  1. Connect Spark Tester (ST-125) to end of one spark plug wire and crank engine. If spark occurs, check other wires. If spark occurs on all plug wires, check fuel delivery.
  2. If spark is not present on all wires, connect scan tester to DLC. Crank engine. If cranking RPM is not displayed on scan tester, go to step 6). If cranking RPM is displayed on scan tester, turn ignition off. Disconnect 6-wire connector at DIS ignition module.
  3. Turn ignition on. Measure voltage between ground and connector Pink/Black ignition switch power supply wire. See Figure. If battery voltage is present, go to next step. If battery voltage is not present, check DIS fuse. If fuse is okay, check for open in Pink/Black wire. If fuse is blown, check for short to ground in Pink/Black wire.
  4. Turn ignition off. Disconnect 5-wire connector from DIS ignition module. Check resistance between ground and Black/White ground wire. If resistance is greater than 200 ohms, repair open in Black/White wire.
  5. If resistance is less than 200 ohms, check for poor ignition module-to-connector harness contact. If okay, replace DIS ignition module.
  6. If cranking RPM is not displayed on scan tester during cranking, turn ignition off. Disconnect 5-wire connector from DIS ignition module. Measure resistance between module harness Yellow and Purple wires (crankshaft position sensor terminals). See Figure.
  7. If resistance is not 700-900 ohms, go to step 10). If resistance is 700-900 ohms, set DVOM on AC volts scale. Connect leads between Yellow and Purple wires at 5-wire harness connector. Crank engine. If voltage is greater than .2 volt, go to next step. If voltage is not greater than .2 volt, check crankshaft position sensor wiring between sensor and DIS ignition module. If harness is okay, replace crankshaft position sensor.
  8. Turn ignition off. Disconnect 6-wire DIS ignition module connector. Turn ignition on. Measure voltage between ground and Pink/Black ignition switch power supply wire of connector. If battery voltage is present, go to next step. If battery voltage is not present, check DIS fuse. If fuse is okay, check for open in Pink/Black wire. If fuse is blown, check for short to ground in Pink/Black wire.
  9. Check DIS ignition module-to-harness connector contact. If connector is okay, replace DIS ignition module.
  10. Remove crankshaft position sensor and measure sensor resistance. If resistance is not 700-900 ohms, replace crankshaft position sensor. If resistance is 700-900 ohms, ensure sensor is still magnetized. If sensor is not magnetized, replace sensor.
  11. If sensor is still magnetized, check crankshaft position sensor harness for open or short to ground.
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