2010 Cadillac CTS Sedan AWD V6-3.0L Page 1527
Circuit/System Description
The engine control module (ECM) uses the generator field duty cycle signal circuit, or F-terminal circuit, to monitor the duty cycle of the generator.
The generator field duty cycle signal circuit connects to high side of the field windings in the generator. A pulse width modulated (PWM) high side
driver in the voltage regulator turns the field windings ON and OFF. The ECM uses the PWM signal input to determine the generator load on the
engine. This allows the ECM to adjust the idle speed to compensate for high electrical loads. The ECM monitors the status of the generator field
duty cycle signal circuit. When the ignition is ON and the engine is OFF, the ECM should detect a duty cycle near 0 percent. When the engine is
running, the duty cycle should be between 5-99 percent.
Conditions for Running the DTC
P0625
* The engine is running.
* The engine speed is less than 3000 RPM.
P0626
* The engine is not running.
* The ignition is in the ON position.
Conditions for Setting the DTC
P0625
The ECM detects a pulse width modulated (PWM) signal less than 5 percent for 15 seconds.
P0626
The ECM detects a pulse width modulated (PWM) signal greater than 65 percent for 15 seconds.
Action Taken When the DTC Sets
DTC P0625 and P0626 are a C type DTCs.
Conditions for Clearing the DTC
DTC P0625 and P0626 are a C type DTCs.
Reference Information
Schematic Reference
Starting and Charging Schematics (See: Starting and Charging/Diagrams/Electrical Diagrams)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Description and Operation
Charging System Description and Operation (See: Starting and Charging/Charging System/Description and Operation)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit
Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Wiring Repairs/Wiring Repairs)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code
(DTC) Type Definitions)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning)for scan tool information
Circuit/System Verification
