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Diagnostic Aids

Outside interference such as CB antenna lead near PCM wiring harness may cause false servo position sensor signal and set Code 68.

Fig 1: Code 68, Schematic, Cruise System Problem, Using Tech 1

Fig 2: Code 68, Flow Chart, Cruise System Problem, Using Tech 1

NOTE: Diagnosing Code 68 using this chart requires the use of the GM Tech 1 Bi-Directional Scan Tool.

Fig 3: Code 68 Flow Chart