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Test 3 - Speed/Reference Mark Sensor

NOTE: This test can only be made with an oscilloscope. Adjust workshop oscilloscope using manufacture's instructions.
  1. Connect positive test lead to terminal No. 7 and connect negative test lead to terminal No. 19 of disconnected EZF ignition control unit plug. Turn engine with starter. Screen should display "sine" oscillation of at least 2.5 V (speed) with an integrated higher amplitude (reference mark).
  2. Sensor distance cannot be adjusted. If insufficient (2.5 V speed) or no deflection is displayed on screen, check for improper connections. Check wire resistance at connections or replace sensor. See Fig 1 .
Fig 1: Speed Reference Signal
G35424