GM Service Manual Online
For 1990-2009 cars only

Scan Tool Data Definitions L81

The Scan Tool Data Definitions list contains a brief description of all of the cruise control related parameters that are available on the scan tool.

Battery Voltage: The scan tool displays the battery voltage. The electronic control module (ECM) monitors the battery positive voltage circuit.

Cruise Switch: The scan tool displays On or Off. The ECM monitors the signal circuit of the cruise control On/Off switch. A closed switch is displayed as On.

Cruise Brake Switch: The scan tool displays Applied or Released. The ECM monitors the cruise/brake switch. A closed switch is displayed as Released.

Cruise Resume/Accel: The scan tool displays On or Off. The ECM monitors the signal circuit of the cruise control Resume/Accel switch. A closed switch is displayed as On, when the cruise On/Off switch is ON and the cruise Resume/Accel button is pressed.

Cruise Set/Coast: The scan tool displays On or Off. The ECM monitors the signal circuit of the cruise control Set/Coast switch. A closed switch is displayed as On, when the cruise On/Off switch is ON and the Set/Coast button is pressed.

Brake Switch: The scan tool displays Applied or Released. The ECM monitors the signal circuit of the stop lamp switch. A closed switch is displayed as Applied.

Engine Speed: The scan tool displays RPM. The ECM monitors the CKP sensor and the CMP sensor in order to determine the engine RPM.

Vehicle Speed: The scan tool displays km/h or mph. The ECM monitors the signal circuit of the vehicle speed signal sensor.

Scan Tool Data Definitions L61

Cruise Control Engaged: Displays Yes / No. Indicates that the powertrain control module (PCM) has seen a transition in the engaged circuit.

Cruise Enable: Displays On / Off. Indicates if the PCM is commanding the cruise control module to inhibit cruise control operation because of a non-cruise control event or the vehicle parameters are out of the cruise control enable criteria.

Cruise Brake Switch / Clutch Switch: Displays Released/Applied. Indicates the current state of the Cruise Brake pedal switch circuit. A closed switch (brake pedal released) indicates B+ voltage on the signal circuit. When you apply the vehicle brakes, the scan tool displays Applied. When you release the brake pedal the scan tool displays Released. This allows the cruise control to be resumed.