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Pick-Up Coil

NOTE: Operation of the vacuum mechanism may cause a trigger wheel tooth and the pick-up coil pole piece to align and the ohmmeter pointer to deflect. This deflection should not be interpreted as the result of a faulty pick-up coil.
  1. Identify the 2 pick-up coil lead wires. On most applications, these wires are 1 Green and 1 White. The pick-up coil connector must be disconnected from the module, then an ohmmeter is connected to 1 connector terminal and to the distributor housing. Next, the ohmmeter is connected to both terminals.
  2. Connect external vacuum source to vacuum advance unit. If vacuum advance unit is inoperative, replace unit. Connect an ohmmeter, using mid scale, to either pick-up coil terminal and the distributor housing.
  3. Operate the vacuum pump and observe the ohmmeter throughout vacuum range. Reading should be infinite at all times. If not, replace pick-up coil. See meter "A" in Figure.
  4. Connect ohmmeter to both pick-up coil connector terminals. Operate vacuum pump and observe ohmmeter throughout the vacuum range. Also, flex wires by hand to locate any intermittent defective connections at pick-up coil and at terminals on ends of wires.
  5. The ohmmeter should indicate a constant resistance in the 500-1500 ohm range at all times. If not, replace the pick-up coil. See meter "B" in Fig 1
Fig 1: Distributor Pick-Up Coil Testing Connections
G9013