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Ground Circuit Checks

  1. Turn ignition to the "OFF" position. On all models except 740 GL with Regina EFI, connect an ohmmeter between ground and ECU connector pin No. 5, No. 17, No. 19, and No. 29.
  2. On 740 GL with Regina EFI, connect ohmmeter between ground and ECU connector pin No. 5, No. 17 and No. 19.
  3. On all models, ohmmeter should indicate continuity between all pin terminals being tested.


  1. Turn ignition switch to the "OFF" position. Using an ohmmeter, connect ohmmeter leads between ground and ECU connector pin No. 5, No. 11, No. 15, and No. 25. Ohmmeter should indicate continuity on all pin terminals being tested.
  2. Check for shorts. Connect ohmmeter between ground and ECU connector pin No. 12 and No. 22. Ohmmeter should read infinity (no continuity) at both terminals.
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