C0800
DTC C0800
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) 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
Diagnostic Fault Information
Circuit/System Description
The adaptive cruise module (ACM) monitors the Ignition 1 voltage circuit to determine if the voltage is within the normal operating range. When the ACM detects that the Ignition 1 voltage is below 9.2 volts or above 16 volts, the DTC C0800 sets.
Conditions for Running the DTC
* Ignition is in RUN.
* Vehicle moving at a speed greater than 40.2 km/h (25 mph).
Conditions for Setting the DTC
C0800 03
* The ACM detects that the ignition 1 voltage is less than 9.2 volts.
* The above condition is present for 7 seconds.
C0800 07
* The ACM 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
The following actions occur:
* Loss of adaptive cruise function
* The DIC displays the Cruise Not Ready message.
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 ACM receives a clear code command from the scan tool.
Diagnostic Aids
* A high or low voltage DTC set in multiple modules indicates a concern in the charging system.
* A possible cause of this DTC could be overcharging with a battery charger or jump starting.
* A high or low voltage value in multiple modules indicates a concern in the charging system.
Reference Information
Schematic Reference
Cruise Control Schematics (Conventional) (Cruise Control Schematics (Conventional))Cruise Control Schematics (Adaptive) (Cruise Control Schematics (Adaptive))
Connector End View Reference
Component Connector End Views (Connector Views)
Electrical Information Reference
* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Circuit/System Verification
1. Verify DTC C0800 is set as current.
2. Engine running, measure and record the voltage at the battery terminals.
3. Verify that the battery voltage is 12.6-15.5 volts.
• If the battery voltage is not within the specified range, refer to Charging System Test (Charging System Test)
4. Engine running, observe the scan tool ignition voltage signal parameter.
5. Verify that the scan tool displays a value that is within 2 volts of the battery terminal voltage.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the adaptive cruise module (ACM).
2. Ignition OFF, test for less than 3 ohms between the ground circuit terminal 12 and ground.
• If greater than the specified value, test the ground circuit for an open/high resistance.
3. Ignition ON, verify a test lamp illuminates between the Ignition 1 voltage circuit terminal 14 and ground.
• If the test lamp did not illuminate , test the circuit for an open/high resistance.
4. If all circuits test normal, test or replace the ACM.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
Control Module References (Programming and Relearning) for ACM replacement, setup, and programming