4 service lights come on and when they do I loose those functions . abs traction stability variable effort steering and some times the display for the radio flickers and becomes jumbled

Most likely reason, IMO, would be an antilock brake sensor(s) or wiring that was damaged or re-installed improperly when the bearings were replaced. If there's no signal from a sensor, that definitely triggers ABS and traction control warnings -- and probably the others, too. If the bearings were replaced by an auto repair place, make them fix it. It's OK to drive the car -- the regular brakes will still work properly, but you won't have the antilock function or traction control.

abs problems will effect ves-- tcs --cruise control -braking system check and test fuses relays wiring sensor and hubs

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

Your best bet , take it to the dealer .
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

QUICK TAKE TO GARAGE LOCAL AND LOOK AT THIS LINK OK Pontiac Grand Prix GXP Service Stability Traction ABS system is back

problem usually narrows down to abs system problem or hub failing causing problem with abs --have vehicle scanned for the trouble code it will assist you as where to start in repairing problem most auto stores offer this service for free --in the mean time pull the abs fuse so brakes can revert to a normal non abs system till repairs can be made

This vehicle is equipped with the BOSCH 5.3 antilock braking system.
The vehicle is equipped with the following braking systems:
• Antilock Brake System (ABS)
• Dynamic Rear Proportioning (DRP)
• Traction Control System (ETS) (w/NW7)
• Traction Control System (TCS) (w/NW9)
• Vehicle stability enhancement system (VSES) You need to have vehicle checked for DTC'S diagnostic trouble codes , do you know what they are ? The traction control , ABS an stability control are all a function of the electronic brake control system .It also seams the power steering is controlled by the Antilock brake system.The Magnasteer® is controlled through the ABS module and varies the torque by adjusting the current flow through the actuator.
Your best place to start would be to have ABS module scanned for DTC'S . Codes would point you in right diagnostic direction .
The following components are involved in the operation of the above systems:
• Electronic Brake Control Module (EBCM), The EBCM controls the system functions and detects failures.
The EBCM contains the following components:
- System Relay, The system relay is energized when the ignition is ON and no ABS DTCs are present. It supplies battery positive voltage to the solenoid valves and pump motor.
- Vent Tube, The vent tube, located in the EBCM, is an opening to the internal cavity of the EBCM. It allows ventilation of the EBCM internals.
• Brake Pressure Modulator Valve (BPMV), The BPMV contains the hydraulic valves and pump motor that are controlled electrically by the EBCM. The BPMV uses a 4 circuit configuration with a diagonal split. The BPMV directs fluid from the reservoir of the master cylinder to the left front and right rear wheels and fluid from the other reservoir to the right front and left rear wheels. The diagonal circuits are hydraulically isolated so that a leak or malfunction in one circuit will allow continued braking ability on the other.

jack up the four points of the vehicle one at a time shake the tire up to down and left to right, you have bad hub assemblies which tells you your ABS IS BAD take it from there and see what lights disappear, keep me posted and we will go from there.

i have an ABS, Traction Control, and Variable Steering warning lights come on right after i put the car in drive and move forward.
2005 Pontiac Grand Prix