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Home >> Plymouth >> 1981 >> Horizon Base, 1.7L Eng VIN A, Automatic Trans >> Repair and Diagnosis >> Engine Performance >> Ignition System >> Hall Effect Electronic Spark Control System >> Testing >> Failure To Start Test
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Failure To Start Test

NOTE: Perform Ignition System Starting Test  first. Failure to do so may result in lost diagnostic time or incorrect test results.
  1. Measure and record battery voltage. Check battery specific gravity, which must be 1.220 (temperature corrected) to deliver proper voltage to ignition system.
  2. Remove coil secondary wire from distributor cap, and hold 1/4" from a good ground. Prepare a special jumper wire assembly as shown in Fig 1. With ignition switch turned on, momentarily touch special jumper wire to ground and coil negative terminal. A spark should be obtained at secondary wire.
    Fig 1: Special Jumper Wire Assembly for Grounding Coil Negative Terminal
    G09317957Courtesy of CHRYSLER GROUP, LLC
  3. If spark was obtained, proceed to step  6). If no spark resulted, turn ignition switch off and disconnect 10-wire harness connector from computer. See Fig 2. Turn ignition switch back on and again, using special jumper, connect negative terminal momentarily to ground. Spark should be obtained.
  4. If spark was obtained, but engine will not start, computer output is shorted. Replace computer. If no spark resulted in step  3), connect positive lead of voltmeter to coil positive terminal and negative lead to a good ground. Reading should be within 1 volt of battery voltage. If not, check wiring between battery and coil positive terminal.
    Fig 2: Distributor and Computer Harness Connectors Used in Testing ESC System
    G09317958Courtesy of CHRYSLER GROUP, LLC
  5. If correct voltage was recorded in step  4), measure voltage between ground and coil negative terminal. Again, it should be within 1 volt of battery voltage. Replace ignition coil if there is either no voltage present, or if voltage is present but no spark results when shorting negative coil terminal.
  6. If no spark was obtained in step  2), or if in step  5) voltage was obtained but engine would not start, hold carburetor switch open with a thin cardboard insulator. See Fig 3. Measure voltage between carburetor switch and ground. Reading should be at least 5 volts. If so, proceed to step  10).
    Fig 3: Location of Carburetor Switch
    G09317959Courtesy of CHRYSLER GROUP, LLC
  7. If voltage was not at least 5 volts in step  6), turn ignition switch off and disconnect 10-wire harness connector from computer. Turn ignition switch on. Connect positive lead of voltmeter to cavity 2 of connector and negative lead to ground. Reading should be within 1 volt of battery voltage.
  8. If no battery voltage is present, check wire from battery to ignition switch to cavity 2. Use an ohmmeter if necessary to check continuity of wires. Correct problem and repeat step  7). If voltage was present in step  7), turn ignition switch off and connect ohmmeter leads to carburetor switch terminal and cavity 7 of 10-wire connector.
  9. If no continuity is found, check for open wire between cavity 7 and carburetor switch. If continuity was indicated, connect ohmmeter leads to cavity 10 and to a good ground. If continuity exists, replace computer, as correct power is entering computer but not leaving it. Repeat step  6). If no continuity existed between cavity 10 and ground, check for an open wire in the ground system.
  10. Reconnect 10-wire harness connector to computer. Turn ignition switch on and hold secondary coil wire 1/4" from a good ground. Disconnect 3-wire distributor connector from distributor. Attach jumper wire between cavities 2 and 3 of distributor harness connector. A good spark should jump from coil wire to ground.
  11. If spark resulted, but engine will not start, replace Hall Effect pick-up. Before replacing pick-up, however, always be sure rotor shutterblades are grounded. Connect one ohmmeter lead to a good ground and touch other lead to shutterblade. See Figure. If no continuity is indicated, push down on rotor to seat against shaft. If still no continuity, replace rotor. If shutter-blade is grounded, then proceed to replace Hall Effect pick-up.
  12. If no spark resulted in step  10), connect voltmeter positive lead to distributor harness connector cavity 1 (Orange wire) and negative lead to ground. Reading should be within 1 volt of battery voltage. If no battery voltage is present, proceed to step  15). If voltage was correct, turn off ignition switch and disconnect 10-wire harness connector from computer.
  13. Connect ohmmeter leads between cavity 2 (Black-Light Blue wire) of distributor harness connector and cavity 9 of 10-wire connector. Then connect leads to cavity 3 (Gray wire) of distributor harness connector and cavity 5 of 10-wire connector. Continuity should be indicated.
  14. If no continuity is present, repair open wires. If continuity exists, replace computer (power going into computer, but not coming out). Repeat step  10).
  15. If there was no battery voltage in step  12), turn ignition switch off, disconnect 10-wire connector, and connect ohmmeter leads to cavity 1 of distributor harness and cavity 3 of 10-wire connector. If no continuity exists, repair wire and repeat step  10).
  16. If continuity existed in step  15), turn ignition switch on and check for battery voltage with voltmeter positive lead in cavity 2 of 10-wire connector and negative lead in cavity 10. If battery voltage is present, but vehicle will not start, replace computer and repeat step  10). If no battery voltage is read, check ground wire and repeat step  10).
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