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Knock Sensor Test

  1. Connect Test Lamp (US 1115 ) to battery positive terminal and to terminal 1 (single connector with Blue wire). See Fig 1. Test lamp Light Emitting Diode (LED) must light up.
  2. Start and accelerator engine to over 3000 RPM (1 time only). Test lamp LED must go off. If LED goes out, knock sensor test is completed.
  3. If LED does not go out, connect a jumper wire between terminal 1 and ground for a minimum of 3 seconds. Test lamp LED must start blinking. If lamp blinks in intervals of 2, the knock sensor circuit is defective.
  4. Check knock sensor tightness. If loose, tighten knock sensor to 96 INCH lbs. (11 Nm). Check for open circuit in knock sensor wiring. If wiring is okay, knock sensor and/or control unit is defective.
Fig 1: Knock Sensor Test
G34272