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Ignition Control Unit

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  1. Perform SPARK TEST in BASIC TESTING article in the ENGINE PERFORMANCE Section. If secondary spark is present, ignition control unit is okay. If secondary spark is not present, turn ignition off. Disconnect ignition control unit wire harness connector. Turn ignition on. Using a voltmeter, measure voltage between terminals No. 2 (-) and No. 4 (+) of connector. See Fig 1 .
  2. Voltage should be present. If voltage is not present, ensure continuity exists between control unit connector terminal No. 2 and ground. Continuity should also exist between terminal No. 4 and ignition coil positive terminal. Repair wiring if necessary. If wiring is okay, replace ignition control unit.
Fig 1: Identifying Typical Ignition Control Unit Connector
G121515Courtesy of VOLKSWAGEN UNITED STATES, INC.
NOTE: Knock control is integral in AFC-Digifant ECU.