If after a service garage replaced the anti-lock brake control unit on a Saturn the traction control will not work are the two related and if so what is the remedy?

Sensors on the wheels determine if the wheels are moving at the approximate same speed. During braking, if one wheel locks up, the brakes will start to pulse, allowing the locked wheel or wheels to start turning again and return control of the steering. The same basic principle is used during accelleration. If one wheel starts to spin considerably faster than the others, the ignition is briefly disconnected, reducing the accelleration rate and allowing the tire to stop spinning. The two processes share the same wheel sensors as well as many other parts of the control system. Yes, the two are definitely related. It may be something as simple as a loose connection or something as complex as a faulty module. Unfortunately, the best way to determine what is wrong with the traction control would be to have the vehicle connected to a diagnostic unit that can check the brakes and onboard control computer. This can be done at an independent repair shop, and if the vehicle is out of warranty, it will probably be a bit expensive.