GM Service Manual Online
For 1990-2009 cars only

The Electronic Suspension Control (ESC) Scan Tool Data Definitions contains a brief description of all ESC related parameters available on the scan tool.

Battery Voltage Signal: The scan tool displays 0-26.0 volts. The battery voltage represents the system voltage measured at the controller battery input.

DSP Software Version: The scan tool displays the controller DSP software version number for service identification.

EEPROM Calibration ID: The scan tool displays the controller EEPROM calibration ID number for service identification.

GM Part Number: The scan tool displays the controller part number for service identification.

GMSCM Software Version: The scan tool displays the controller GMSCM software version number for service identification.

LF Damper Actuator Command: The scan tool displays 0-100%. This percentage represents the commanded state of the shock absorbers. When the ESC system commands the shock absorbers ON, the percentage will increase. When the ESC system commands the shock absorbers OFF, the percentage will decrease.

LF Normal Force: The scan tool displays 20-80%. This percentage represents a measured level of the road surface sent from the Electronic Suspension Control (ESC) module to the Electronic Brake Control Module (EBCM). The EBCM uses this information to improve braking during various rough road conditions.

LF Position Sensor: The scan tool displays 0-5.0 volts. The position sensor is a variable resistor which changes with vehicle trim height. The ESC system uses this voltage reading to determine different road and driving conditions. The ESC system adjusts the damping level in each shock absorber based upon the voltage level received back from all four position sensors.

LR Damper Actuator Command: The scan tool displays 0-100%. This percentage represents the commanded state of the shock absorbers. When the ESC system commands the shock absorbers ON, the percentage will increase. When the ESC system commands the shock absorbers OFF, the percentage will decrease.

LR Position Sensor: The scan tool displays 0-5.0 volts. The position sensor is a variable resistor which changes with vehicle trim height. The ESC system uses this voltage reading to determine different road and driving conditions. The ESC system adjusts the damping level in each shock absorber based upon the voltage level received back from all four position sensors.

Lift/Dive Change: The scan tool displays Changed or Unchanged. The ESC system receives chassis pitch input from the PCM. When there is a change in chassis pitch status , the scan tool will display Changed. If there is not change, the scan tool will display Unchanged.

Lift/Dive Status: The scan tool displays Active or Inactive. The ESC system receives chassis pitch input from the PCM. The scan tool will display Active when the ESC system detects a change in chassis pitch status. When there is no change in chassis pitch, the scan tool will display Inactive.

RF Damper Actuator Command: The scan tool displays 0-100%. This percentage represents the commanded state of the shock absorbers. When the ESC system commands the shock absorbers ON, the percentage will increase. When the ESC system commands the shock absorbers OFF, the percentage will decrease.

RF Normal Force: The scan tool displays 20-80%. This percentage represents a measured level of the road surface sent from the Electronic Suspension Control (ESC) module to the Electronic Brake Control Module (EBCM). The EBCM uses this information to improve braking during various rough road conditions.

RF Position Sensor: The scan tool displays 0-5.0 volts. The position sensor is a variable resistor which changes with vehicle trim height. The ESC system uses this voltage reading to determine different road and driving conditions. The ESC system adjusts the damping level in each shock absorber based upon the voltage level received back from all four position sensors.

RR Damper Actuator Command: The scan tool displays 0-100%. This percentage represents the commanded state of the shock absorbers. When the ESC system commands the shock absorbers ON, the percentage will increase. When the ESC system commands the shock absorbers OFF, the percentage will decrease.

RR Position Sensor: The scan tool displays 0-5.0 volts. The position sensor is a variable resistor which changes with vehicle trim height. The ESC system uses this voltage reading to determine different road and driving conditions. The ESC system adjusts the damping level in each shock absorber based upon the voltage level received back from all four position sensors.

Steering Position PWM: The scan tool displays 0-10 ms. This PWM signal is sent by the ABS system which changes when the steering wheel is turned. The ESC system uses this PWM signal to determine the shock absorber control levels and will command a more firm setting if the vehicle is turning.

Vehicle Speed: The scan tool displays 0-255 km/h (0-159 mph). The ESC system obtains vehicle speed data from the PCM via Class 2.