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DFI ECM Tests W/Codes: Action:

Cruise control disengaged.

Code E063 will be set if vehicle speed is 20 MPH higher or lower than the vehicle set speed. This code is used as a type of safety valve to the cruise control system. System can be set under normal conditions if driver accelerates and goes over 20 MPH over set cruise speed.

NOTE: Test numbers refer to test numbers on diagnostic chart.
  1. This steps checks cruise control servo's ability to pull in and stay in.
  2. This step checks to see if vacuum leak is due to brake release valve and/or circuit, or servo and/or vacuum source.
  3. This step checks to see if vacuum leak is due to vacuum source or servo.
  4. This steps checks to see if fault is due to intermittent or slow vacuum leak.
  5. This steps checks to see if fault is servo or brake vacuum release circuit.
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