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Knock Sensor Control Unit (All Models Except VANAGON)

NOTE: Knock control is integral in AFC-Digifant II ECU.
  1. Check ignition coil and Hall Effect sender before checking knock sensor control unit. Remove knock sensor control unit harness connector. Turn ignition on. Using a voltmeter, check for battery voltage between terminals No. 3 and No. 5 and terminals No. 6 and No. 3 of knock sensor control unit. Open throttle valve. Voltage should drop to zero volts.
  2. If voltage does not drop to zero volts, check throttle valve switch (full throttle). Check voltage between terminals No. 8 and No. 3, while fully opening throttle valve. If battery voltage was not present when throttle fully open, replace throttle valve switch. See Figure .
  3. Remove Hall Effect sender connector and connect voltmeter to outside terminals. Turn ignition on. There should be 5 volts present. Turn ignition off. Connect voltmeter between terminals No. 1 (negative) and No. 15 (positive) of ignition coil. Turn ignition on and touch center terminal of Hall Effect sender briefly to ground. Voltage should jump momentarily to approximately 2 volts. If voltage does not jump, replace knock sensor control unit.
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