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Omni and Horizon Models

  1. Measure and record battery voltage. Battery specific gravity must be at least 1.220 (temperature corrected) to deliver proper voltage to cranking (ignition) system.
  2. Disconnect wire from negative terminal of coil. Remove coil secondary wire from distributor cap. Connect jumper wire to coil negative wire.
  3. Turn ignition "ON". Using jumper wire, quickly touch negative terminal of coil to ground while holding coil secondary wire 1/4" from good engine ground. A spark should be obtained.
  4. If no spark, make the following checks:
    • Check coil positive terminal voltage; should be at least 9 volts.
    • If voltage is correct, coil is defective and should be replaced.
    • If voltage is incorrect, check and repair wiring and/or connections as required.
    • If vehicle still will not start, proceed to step 5)  .
  5. If spark was obtained, turn ignition "OFF" and reconnect coil. Disconnect 3-wire connector from computer at distributor. Turn ignition "ON" and measure voltage from pin "B" to engine ground. Voltage should be battery voltage. See Fig 1.
  6. If voltage was correct, proceed to step  9. If voltage was incorrect, turn ignition "OFF" and disconnect 10 pin connector at computer.
    NOTE: All tests are made through 10 pin connector at computer and 3 pin connector at distributor unless otherwise noted.
  7. Check continuity between pin "3" and pin "B". If no continuity exists, repair wiring and/or connections. If continuity exists, proceed to step 8)  .
    NOTE: There must be at least 1/4" layer of multi-purpose grease on 10-wire connector and connector cavity. Do not remove grease. Reapply if necessary.
  8. Turn ignition "ON", check for battery voltage between pins "2" and "10". If voltage is same as battery voltage, spark control computer is defective and should be replaced. If voltage is not same as battery voltage, check and repair wiring and/or connections.
  9. Reconnect 10 pin connector to computer. Hold coil secondary wire 1/4" from ground and turn ignition "ON". Use jumper wire to momentarily touch pins "A" and "C" together and check the following:
    • If coil wire sparks, Hall Effect pick-up coil assembly is defective.
    • If coil wire does not spark, proceed to step 10)  .
    Fig 1: Disconnecting Wiring Harnesses for Tests (Pin Locations Shown)
    G09339803Courtesy of CHRYSLER GROUP, LLC
  10. Turn ignition "OFF", disconnect 10 pin connector from computer. Using ohmmeter, check continuity as follows:
    • Pin "C" to pin "9".
    • Pin "A" to pin "5".
    • If continuity exists with these checks, spark control computer is defective and should be replaced.
    • If continuity does not exist, wiring and/or connections are shorted or broken, repair as required.
    • After repairs are made, go back and repeat step  8.
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