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Test NS-4A - Inspecting Ignition

WARNING: This page is about a different car, the 1995 Dodge Ram Wagon, 1995 Dodge Ram Van, 1995 Dodge Pickup, and 1995 Dodge Dakota. However, it is still accessible from the selected car via links, so may be relevant.
  1. Turn ignition off. Disconnect any spark plug cable at spark plug. Insert insulated screwdriver in spark plug cable terminal.
    CAUTION: Damage to Powertrain Control Module (PCM) may occur if screwdriver is held more than 1/4" from ground
  2. Hold screwdriver within 1/4" of a good ground. Watch for spark while cranking engine for 10 seconds. Ensure spark is present. One or 2 sparks is considered a no-spark condition. If good spark is not present, go to next step. If good spark is present and engine starts and stalls repeatedly, go to TEST NS-7A. If good spark is present and engine does not start, go to TEST NS-5A.
  3. Reconnect spark plug cable.
    CAUTION: Damage to Powertrain Control Module (PCM) may occur if coil secondary cable is held more than 1/4" from ground
  4. Turn ignition off. Remove coil secondary cable from distributor. Hold coil secondary cable within 1/4" of a good ground. Watch for spark while cranking engine for 10 seconds. Ensure spark is present. One or 2 sparks is considered a no-spark condition. If good spark is present, repair secondary ignition (distributor cap, rotor, cables). Perform TEST VER-1.
  5. If good spark is not present, turn ignition off. Remove coil secondary cable. Using an external ohmmeter, check resistance of coil secondary cable. If resistance is more than 15 k/ohms, replace coil secondary cable. Perform TEST VER-1.
  6. If resistance is less than 15 k/ohms, remove distributor cap. Watch rotor turn while cranking engine for 10 seconds. If rotor does not turn with engine cranking, repair distributor drive system. Perform TEST VER-1.
  7. If rotor turns with engine cranking, reinstall distributor cap and ignition coil cable. Disconnect and inspect Crankshaft Position (CKP) sensor connector. Repair connector as necessary. Perform TEST VER-1. If connector is okay, go to next step.
  8. Turn ignition on. Using scan tool in voltmeter mode, check voltage on CKP sensor connector, 8-volt supply circuit (Orange wire). If voltage is more than 7 volts, go to step 11).
  9. If voltage is less than 7 volts, disconnect and inspect Camshaft Position (CMP) sensor connector. Repair connector as necessary. Perform TEST VER-1. If connector is okay, check voltage on CMP sensor connector, 8-volt supply circuit (Orange wire). If voltage is more than 7 volts, replace CMP sensor. Perform TEST VER-1.
  10. If voltage is less than 7 volts, turn ignition off. Disconnect and inspect PCM connector. Repair connector as necessary. Perform TEST VER-1. If connector is okay, put scan tool in ohmmeter mode. Using scan tool, check resistance of PCM connector terminal No. 7, 8-volt supply circuit (Orange wire). If resistance is less than 5 ohms, replace PCM. Perform TEST VER-1. If resistance is more than 5 ohms, repair open Orange wire. Perform TEST VER-1.
  11. Reconnect CKP sensor connector. Disconnect and inspect Camshaft Position (CMP) sensor connector. Repair connector as necessary. Perform TEST VER-1. If connector is okay, check voltage on CMP sensor connector, 8-volt supply circuit (Orange wire). If voltage is more than 7 volts, go to step 13).
  12. If voltage is less than 7 volts, turn ignition off. Disconnect PCM connector. Using an external ohmmeter, check resistance of 8-volt supply circuit (Orange wire) between PCM connector terminal No. 7 and CMP sensor connector. If resistance is less than 5 ohms, replace CKP sensor. Perform TEST VER-1. If resistance is more than 5 ohms, repair open Orange wire. Perform TEST VER-1.
  13. Disconnect and inspect ignition coil connector for damaged, pushed-out or miswired terminals. Repair as necessary. Perform TEST VER-1. If connector is okay, turn ignition on. Using scan tool, actuate fuel system.
  14. Using scan tool in voltmeter mode, check voltage on ignition coil connector, ASD relay output circuit (Dark Green/Orange wire). If voltage is less than 10 volts, repair open in Dark Green/Orange wire. Perform TEST VER-1.
  15. If voltage is more than 10 volts, check voltage on ignition coil connector, ignition coil driver circuit (Gray wire). If voltage is more than 10 volts, go to step 20). If voltage is less than 10 volts, turn ignition off.
  16. Disconnect and inspect PCM connector. Repair as necessary. Using scan tool in ohmmeter mode, check resistance of PCM connector terminal No. 19, ignition coil driver circuit (Gray wire on AB and AN bodies; Black/Gray wire on BR body). If resistance is less than 5 ohms, repair short to ground in Gray wire or Black/Gray wire. Perform TEST VER-1.
  17. If resistance is more than 5 ohms, use an external ohmmeter to check resistance of ignition coil driver circuit (Gray wire on AB and AN bodies; Black/Gray wire on BR body) between PCM connector terminal No. 19 and ignition coil connector. If resistance is more than 5 ohms, repair open in Gray wire or Black/Gray wire from PCM to ignition coil. Perform TEST VER-1. If resistance is less than 5 ohms, replace PCM. Perform TEST VER-1.
    NOTE: Following steps require an analog voltmeter capable of reading a 0.1 volt pulsation.
  18. Using scan tool, stop actuation test. Check valve timing. Correct valve timing as necessary. Perform TEST VER-1. If valve timing is okay, connect an analog voltmeter between ignition coil connector, ASD relay output circuit (Dark Green/Orange wire) and ground.
  19. Using scan tool, actuate ignition coil. If voltmeter pulsates, replace ignition coil. Perform TEST VER-1. If voltmeter does not pulsate, replace PCM. Perform TEST VER-1.
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