GM Service Manual Online
For 1990-2009 cars only
Cruise Control Active: Displays Yes or No. The status of the cruise engaged signal. The cruise control module grounds the circuit when cruise control is on.

Cruise Release Clutch/TCC Pedal Switches: Displays Applied or Released.The status of the cruise release signal circuit. The TCC/brake pedal switch and the clutch pedal position (CPP) switch if equipped, are normally closed switches, in series, controlling the cruise control cancel circuit.

Vehicle Speed Sensor: Displays km/h and mph. The vehicle speed sensor signal is converted into km/h and mph for display.