GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2007 🢒 STS 🢒 DTC 🢒 DTC C0800

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC C0800 03: Device Power 1 Circuit Voltage Below Threshold

DTC C0800 07: Device Power 1 Circuit Voltage Above Threshold

Circuit/System Description

The distance sensing cruise control (DSCC) module monitors the ignition 1 voltage circuit in order to determine if the voltage is within the normal operating range. When the DSCC module detects that the ignition 1 voltage is below 9.2 volts or above 16 volts, DTC C0800 sets.

Conditions for Running the DTC

C0800 03 and 07

    • Ignition is in RUN.
    • Vehicle speed is greater than 40.2 km/h (25 mph).

Conditions for Setting the DTC

C0800 03

    • The DSCC module detects that the ignition 1 voltage is less than 9.2 volts.
    • The above condition is present for 7 seconds.

C0800 07

    • The DSCC module detects that the ignition 1 voltage is greater than 16 volts.
    • The above condition is present for 7 seconds.

Action Taken When the DTC Sets

C0800 03 and 07

The following actions occur:

    • Loss of adaptive cruise function
    • Cruise Not Ready indicator illuminates in the DIC.

Conditions for Clearing the DTC
    • The DTC becomes history when the fault is no longer present.
    • A History DTC clears after 100 malfunction-free ignition cycles.
    • The DSCC receives a clear code command from the scan tool.

Diagnostic Aids
    • Using the Failure Records data may help locate an intermittent condition. If you cannot duplicate the DTC, the information in the Failure Records can help determine how many miles since the DTC set. The Fail Counter and Pass Counter can help determine how many ignition cycles that the diagnostic test reported a pass and/or a fail.
    • A possible cause of this DTC could be overcharging with a battery charger or jump starting.
    • A low voltage DTC in multiple modules indicates a concern in the charging system.
    • A high voltage value in multiple modules indicates a concern in the charging system.

Reference Information

Schematic Reference

Cruise Control Schematics

Connector End View Reference

Master Electrical Component List

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Scan Tool Data List

Circuit/System Verification
  1. Ignition ON, verify that no low system voltage DTCs are not set as current.
    2. ⇒If other DTCs are set as a current DTC, refer to Diagnostic Trouble Code (DTC) List - Vehicle
  2. Verify that DTC C0800 is current in the scan tool.
    3. ⇒If the DTC is set as history refer to Charging System Test .
    ⇒If the DTC is set as current, go to Circuit/System Testing.

Circuit/System Testing
  1. Ignition OFF, disconnect the harness connector at the distance sensing cruise control (DSCC) module.
  2. Ignition OFF, test for less than 1.0 ohm of resistance between the ground circuit terminal 6 and ground.
    3. ⇒If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, test for greater than 9.2 volts between the ignition 1 voltage circuit terminal 1 and ground.
    4. ⇒If less than the specified value, test the circuit for an open/high resistance.
  4. If all circuits test normal, test or replace the DSCC module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for DSCC module replacement, setup, and programming