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Test 2 - Testing System When Engine Will Not Start

  1. Disconnect high tension wire at distributor cap. Hold wire 1/2" from engine block. Crank engine and if spark occurs, check rotor and distributor cap. Ensure spark is reaching spark plugs.
  2. If no spark occurs, disconnect connector at distributor. Connect jumper wire to pin "A" in the control unit connector. See Fig 1 . With ignition in the "ON" position, touch pin "C" with the other end of jumper wire and check for spark at the high tension wire end.
    Fig 1: Distributor Connector Showing Pin Locations
    G48624
  3. If no spark occurs, proceed to step 4). If spark occurs, touch jumper wire between pin "A" and pin "C", and check for "live" condition at pin "B". If voltage is present, install new Hall Sending Unit in distributor. If no voltage is present, ensure wiring harness is good. If harness is OK, replace ECU.
  4. If no spark occurred in step 2), check all wires and connectors carefully. If no fault is found, substitute a new ignition coil. If there is still no spark, substitute a new control unit.