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Ignition Control Unit

  1. Remove connector from ignition control unit (forward of left wheel housing) and connect voltmeter to connector terminals No. 2 and 4. Turn ignition on. Voltage should read about 12 volts. If voltage is not present, repair open in terminal No. 2 (ground circuit) or open or short in circuit No. 15 (wire from positive side of ignition coil).
  2. Reconnect ignition control unit connector. Disconnect coil wire from distributor cap center terminal and connect to ground using a jumper wire. Remove protective cover to gain access to rear of control unit connector.
  3. Connect digital voltmeter across rear of connector at terminals No. 3 and 6 of the control unit (4 and 6 on models with knock control unit). Turn ignition switch to "START" position. Voltage should be displayed while cranking engine. If NO voltage is displayed, see HALL EFFECT SENDING UNIT  test.
  4. Turn ignition off. Disconnect 3-wire connector from distributor on all models. Connect positive voltmeter lead to terminal No. 15 of coil. Connect negative voltmeter lead to terminal No. 1 of coil.
  5. Turn ignition on. Voltmeter should show voltage and must drop to zero volts within 1-2 seconds. If voltage does not drop, replace Hall control unit. If voltage drops, install short jumper lead to center terminal of distributor 3-wire connector. Lightly tap lead to ground. Voltage must rise to a minimum of 2 volts for a short time. If voltage rise is not indicated, replace Hall control unit.
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