2003 cadilliac cts service steering message how to fix or clear it

SERVICE STEERING SYS
Refer to Variable Effort Steering System Description and Operation in Variable Effort Steering

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Variable Effort Steering System Description and Operation
The Variable Effort Steering (VES) System varies the amount of effort to steer the vehicle as wheel speed changes or lateral acceleration occurs. The Electronic Brake Control Module (EBCM) controls an actuator located in the steering rack and pinion. The actuator consists of an electromagnetic coil and a pintle valve which moves in and out of the rack and pinion's input fluid orifice, regulating power steering fluid flow. The EBCM commands current from 0-1 amp to the VES actuator which varies the amount of effort to steer the vehicle. At low speeds, 1 amp of current is commanded to the VES actuator and the pintle valve is fully retracted which provides maximum fluid flow and maximum steering assist for easy turning and parking maneuvers. At high speeds, no current is commanded and the pintle valve moves closer to the orifice, decreasing fluid flow, providing firmer steering (road feel) and directional stability. The VES system uses the steering wheel position sensor input to calculate lateral acceleration during abrupt driving maneuvers. The system also uses the Antilock Brake System (ABS) wheel speed sensor inputs to determine vehicle speed. The EBCM is constantly monitoring these inputs to achieve the desired current to the VES actuator. The EBCM has the ability to detect malfunctions in the VES actuator or the circuits to the actuator. Any malfunctions detected will cause the VES outputs to be disabled and the EBCM will command the Driver Information Center (DIC) to display the SERVICE STEERING SYSTEM warning message via a class 2 serial data circuit.
Step
Action
Yes
No
Schematic Reference: Steering Assist Schematics
1
Install a scan tool.
Does the scan tool turn ON?
Go to Step 2
Go to Scan Tool Does Not Power Up in Data Link Communications
2
Turn ON the ignition, with the engine OFF.
Attempt to establish communication with the EBCM.
Does the scan tool communicate with the EBCM?
Go to Step 3
Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications
3
Select the ABS Diagnostic Trouble Codes function on the scan tool.
Does the scan tool display any DRP/ABS/TCS or VSES DTCs?
Go to Diagnostic System Check - ABS in Antilock Brake System
Go to Step 4
4
Does the scan tool display any DTCs which begin with a "U"?
Go to Diagnostic Trouble Code (DTC) List in Data Link Communications
Go to Step 5
5
Does the scan tool display "DTC C0450?"
Go to Diagnostic Trouble Code (DTC) List
System OK