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Normal Operation

For all speed control systems, the PCM sends a signal through circuit VES10 (WH) to the speed control switches which passes through the clockspring. The return signal is sent through circuit RES08 (GN/BN) and the clockspring. The speed control system deactivates when the brake pedal is applied or the speed control OFF switch is pressed. On vehicles with the adaptive cruise control system, the Cruise-Control Module (C-CM) communicates with the Instrument Panel Cluster (IPC), ABS module and PCM over the High Speed Controller Area Network (HS-CAN). A fault in the C-CM  causes an inoperative condition for the speed control system and a message is displayed in the message center.

DTC DESCRIPTION CHART

DTC Description Fault Trigger Conditions
  • U0121:00 - Lost Communication With Anti-Lock Brake System (ABS) Control Module: No Subtype Information
A continuous DTC that sets when the C-CM  does not receive the electronically-controlled deceleration activity status message from the ABS module.
  • U0155:00 - Lost Communication With Instrument Panel Cluster (IPC  ) Control Module: No Subtype Information
A continuous DTC that sets when the C-CM  does not receive the ignition switch position (gateway) message from the IPC  .
  • U2515 - Missing Message for Adaptive Cruise Control
A continuous DTC that sets when the ABS module does not receive the adaptive cruise control brake status message from the C-CM  .
  • U0405 - Invalid Data Received from Cruise Control Module
A continuous DTC that sets when the ABS module receives invalid data from the C-CM  .

This pinpoint test is intended to diagnose the following: