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Basic System Test

  1. If engine will not start and starter will not crank engine, check battery, main fuse and electrical wiring. Check starter circuit wiring and ignition switch. If engine will not start, but starter cranks engine, hold coil wire 1/4" from coil tower while cranking engine.
  2. If there is spark from coil, then hold spark plug wire terminal 1/4" from spark plug while cranking engine.
  3. If there is no spark at the plug, check spark plug wire condition, inspect distributor cap and rotor, and as a last resort, replace ignitor on distributor housing. If spark exists at the plug, check fuel system, spark plugs, ignition timing or valve timing.
  4. If there was no spark at the coil in step 1)  , turn ignition switch to the "ON" position. Check voltage between coil primary winding positive terminal and ground. Battery voltage should be found. If not, check wiring from ignition switch to ignition coil.
    Fig 1: Checking Ignitor Voltage
    G09323527Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Battery voltage should be present in both tests. 

  5. If battery voltage exists, be sure ignition switch is still in the "ON" position. Check voltage between coil primary winding negative terminal and ground. Again, battery voltage should exist. If not, check wiring from coil primary negative terminal to ignitor. Also check coil primary resistance.
  6. If battery voltage was present at negative terminal, check voltage between coil positive and negative terminals with engine cranking. Reading should be 1-3 volts. If within specifications, check primary and secondary coil resistance. Also check spark plug wire resistance.
  7. If voltage in step 6)  was not 1-3 volts, disconnect lead wires from ignitor. Check voltage on coil side of connector, first between blue wire and black (ground) wire and then between black/yellow wire and black (ground) wire. See Fig 1. Battery voltage should exist with ignition switch "ON".
    Fig 2: Checking Continuity at Ignitor Terminals
    G09323528Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Test as shown and then reverse ohmmeter connections. 

  8. If not, check wiring from ignition coil to ignitor. Check continuity between ignitor terminals. See Fig 2. Set ohmmeter to x100 range. Attach positive lead to terminal for black/yellow wire and negative lead to terminal for blue wire. There should be continuity.
  9. Then, reverse ohmmeter leads (positive lead to terminal for blue wire, negative lead to terminal for black/yellow wire). There should be no continuity. If incorrect results are obtained, replace ignitor and repeat test.