GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2007 🢒 XLR 🢒 Driver Information and Entertainment 🢒 Cellular, Entertainment, and Navigation 🢒 DTC C1002

Circuit Description

The forward looking sensor (FLS) has the exclusive function of detecting, tracking and classifying targets within its specified field of view. The FLS has the ability to detect and react to objects of interest in its detection zone and is critical to the proper operation of the Adaptive Cruise Control (ACC) System. When the distance sensing cruise control module (DSCC) detects that the FLS is out of alignment, DTC C1002 sets.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC C1002 Distance Sensing Cruise Control Module Range/Performance

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC
    • 2.5 degrees of skew or error of the FLS
    • Vehicle has been driven for some time

Action Taken When the DTC Sets
    • Loss of ACC function
    • Service Radar Cruise indicator illuminates in the driver information center (DIC).

Conditions for Clearing the DTC
    • The DTC becomes history when the conditions for setting the DTC are no longer present.
    • The history DTC clears after 100 malfunction-free warm-up cycles.
    • The DSCC receives a clear code command from the scan tool.

Diagnostic Aids
    • The FLS radar is equipped with an internal automatic alignment feature. The FLS radar alignment is continuously assessed and adjusted as necessary during ACC vehicle operation by the DSCC. Refer to Cruise Control Description and Operation for more information on the FLS radar automatic alignment feature.
    • When automatic alignment is not achieved by the FLS radar and an out of alignment diagnostic is reported by the DSCC, it is necessary to mechanically align the FLS radar using the FLS alignment tool. Refer to Distance Sensing Cruise Control Aiming to properly align the FLS radar. The typical DSCC alignment value is 0°+/-2°.
    • An FLS radar out of alignment condition may be as a result of tampering with the DSCC mounting structures/brackets or the adjuster settings. An out of alignment condition may be a result of damage to the front section of the ACC vehicle or the DSCC. Refer to Distance Sensing Cruise Control Aiming and Distance Sensing Cruise Control Bracket Replacement to properly adjust or replace the DSCC or the DSCC brackets.
    • An out of alignment condition may be because the FLS radar has not achieved a complete internal automatic alignment. For the FLS radar to achieve a complete automatic alignment and process the road environment correctly, the ACC vehicle needs to be driven on a road with stationary objects (mail boxes, road signs, trees, ramps etc.). The distance that the vehicle needs to be driven to achieve a complete automatic alignment depends on: the number of stationary objects encountered on the road the vehicle is travelling. The more stationary objects encountered, the quicker the FLS radar will achieve automatic alignment. When the DSCC is replaced with a new module, it is necessary to drive the vehicle with the new module until the automatic alignment is complete. Performance of the ACC system may be degraded after DSCC replacement. Normal vehicle driving will correct the performance of the ACC system. Refer to Cruise Control Description and Operation .