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All Models Except Omni and Horizon

  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. Insert a piece of paper between idle adjusting screw and carburetor sensor, or insure screw does not contact sensor. Connect a voltmeter negative lead to ground.
  3. Turn ignition to "RUN" position and measure voltage at the carburetor switch terminal. If voltage is approximately 5 volts, proceed to step  7).
  4. If voltage is not at least 5 volts, turn ignition switch "OFF" and disconnect the 10 pin connector from computer. Turn ignition to "RUN" and measure the voltage at pin 2 of 10 pin connector. Voltage should be battery voltage. If voltage is correct, proceed to step  6). If voltage is not correct, check and repair wiring and connections between pin 2 of 10 pin connector and ignition switch.
  5. Turn ignition switch "OFF" and check continuity between pin 7 of 10 pin connector and carb switch terminal. Continuity should exist. If not, check wire between pin 7 and carburetor switch. If continuity exists, check for continuity between pin 10 of 10 pin connector and ground. If continuity exists, replace computer. If continuity does not exist, check wire from pin 10 ground.
  6. Turn ignition switch to "RUN" position and connect positive lead of voltmeter to pin 1. Connect negative lead to ground. Reading should be battery voltage. If reading is correct, proceed to step  9). If it is not correct, proceed as follows.
  7. Turn ignition switch "OFF". With an ohmmeter, measure resistance between pins 5 and 9 of 10 pin connector for the pick-up assembly (if distributor is equipped with a start pickup, also measure between pins 3 and 9 in the 10 pin connector). Pick-up resistance should be between 150 and 900 ohms. If resistance is correct, proceed with step  10). If resistance is incorrect, proceed with next step.
  8. Disconnect pick-up assembly connector at distributor and measure resistance across the pins of the connector (going to distributor). Resistance should be 150 to 900 ohms. If resistance is now correct, wires between 10 pin connector pins 3, 5, and 9 and pick-up assembly connector are shorted or broken. If resistance is not correct, pick-up assembly is bad and should be replaced.
  9. Connect one lead of an ohmmeter to ground and the other lead to each of the pins of the pick-up assembly connector (going to distributor). No continuity should be indicated. If any continuity is indicated, pick-up assembly is shorted and should be replaced.
  10. Remove distributor cap and check air gap of pick-up assembly (check both pick-up assemblies if equipped). If air gap is incorrect, adjust air gap to specifications (see Pick-Up Coils - Air Gap in this article)  by loosening pick-up hold down screw and moving pick-up assembly.
  11. Install distributor cap and reconnect all wiring. Start vehicle. If vehicle fails to start, install a new computer. If vehicle now starts, install old computer and try to start vehicle. If vehicle starts, system is okay. If not, replace computer. If vehicle would not start when new computer was originally installed, install old computer and repeat test procedures to find fault (probably with testing).
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