2021 Jeep Cherokee High Altitude, Automatic T/Case ControlFACTORY OEM SERVICE PROCEDURE

Sensor, Knock: Operation

GC0152782Courtesy of CHRYSLER GROUP, LLC

The molecules of a quartz crystal are affected by electrical polarization. In rest conditions (A) the molecules are not arranged in a particular way. When the crystal is subjected to pressure or to an impact (B), the higher the pressure, the more marked their arrangement. This arrangement produces a voltage at the ends of the crystal.

Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.