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Home >> GMC >> 2001 >> C 6500 TopKick V8-8.1L VIN E >> Repair and Diagnosis >> Cruise Control >> Testing and Inspection >> Symptom Related Diagnostic Procedures >> Cruise Control Inoperative/Malfunctioning
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Cruise Control Inoperative/Malfunctioning




Cruise Control Inoperative/Malfunctioning

Diagnostic Aids

Important: Perform the following in order to avoid misdiagnosis.


* Inspect for proper operation of brake lamps and clutch switch, if equipped.

* EMI on the speed sensor signal circuit may cause erratic cruise control operation.


Conditions for Enabling Cruise Control

The vehicle speed is greater than 40 km/h (25 mph).

Test Description

The numbers below refer to step numbers on the diagnostic table.
5. The TAC module and PCM receive brake pedal position from the stoplamp interface module, regardless of how many stoplamp switches the vehicle is equipped with.

















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