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Home >> Plymouth >> 1980 >> Arrow Base, Automatic Trans >> Repair and Diagnosis >> Engine Performance >> Ignition System >> Electronic Spark Control System >> Trouble Shooting >> Failure To Start Test >> Omni and Horizon Models
July 1: So it begins. Don't worry, this is not in the correct legal jurisdiction!

Omni and Horizon Models

  1. Measure and record battery voltage. Measure battery specific gravity, which must be at least 1.220 (temperature corrected) to deliver proper voltage to ignition system.
  2. Disconnect wire from negative terminal of coil. Disconnect high tension coil wire from distributor. Hold coil wire about 1/4" from a good engine ground.
    Fig 1: Three Wire Connector from Computer to Distributor (Showing Pin Location)
    G09343310Courtesy of CHRYSLER GROUP, LLC
  3. Turn ignition on. While holding coil high tension wire 1/4" from ground, momentarily touch jumper wire to negative terminal of coil and to ground. Coil high tension wire should spark. If not, make the following checks:
    • No spark, check coil positive terminal voltage. Should be at least 9 volts.
    • If voltage is good, coil is defective.
    • If voltage is not to specifications, check and repair wires and connections as necessary.
    • If car still will not start, proceed to step  4).
  4. If coil sparked in step  3), turn ignition switch off and reconnect coil. Disconnect 3 wire connector from computer to distributor (at distributor). Turn ignition on and measure voltage from pin "B" of 3 wire connector to engine ground. Voltage should be battery voltage. See Fig. 5. 
    Fig 2: Disconnecting 10 Pin Connector from Computer and Showing Locations of Pins on 10 Pin Connector and on 3 Wire Connector from Distributor
    G09343311Courtesy of CHRYSLER GROUP, LLC
  5. If voltage was correct, proceed to step  8). If voltage was not correct, proceed as follows. Turn ignition off and disconnect 10 pin connector at computer. See Fig. 6. 
  6. With 10 pin connector and 3 wire connector disconnected, check continuity between pin 3 of 10 pin connector and pin "B" of 3 wire connector. If there is no continuity, repair wire and see if problem is fixed. If continuity exists, proceed to step  7).
  7. Turn ignition on and check for battery voltage between pins 2 and 10 (ground) of 10 pin connector of computer. If voltage is not same as battery voltage, check wire and connections. If battery voltage is measured at this point, spark control computer is defective and should be replaced.
  8. Connect 10 pin connector to computer. Hold coil wire 1/4" from ground and turn ignition on. On the 3 wire connector (disconnected at distributor), use a jumper wire to momentarily touch pins "A" and "C" together.
    • If coil wire sparks, Hall Effect pick-up assembly is defective.
    • If coil wire does not spark, proceed to step  9).
  9. Turn ignition off and disconnect 10 pin connector from computer. Using an ohmmeter, check the continuity between the following pins: