GM Service Manual Online
For 1990-2009 cars only

The electronic suspension control (ESC) scan tool data display values and definition information that can assist in diagnosing ESC related problems, especially when no diagnostic trouble codes (DTC) are stored in memory. A vehicle's scan tool data can be compared with the data display values from a known good vehicle in the scan tool data display table. When data from the vehicle differs from the typical data display value, the data definition information will help in understanding the nature of the difference and the source of the problem. This list is in alphanumeric order.

Data Definitions

Battery Voltage Signal--Range 10.0-16.0 Volts: This data refers to the battery system voltage as measured by the suspension control module.

Compressor Signal, if equipped -- ON/OFF: This data indicates when the compressor relay is activated.

Digital SWPS Phase A--High/Low: This data indicates the state of phase A in the steering wheel position sensor.

Digital SWPS Phase B--High/Low: This data indicates the state of phase B in the steering wheel position sensor.

Exhaust Signal, if equipped -- ON/OFF: This data indicates when the exhaust solenoid is commanded On or Off.

Left Front Damper Actuator--ON/OFF: This data refers to the state of the suspension damper solenoid contained within the shock absorber.

Left Rear Damper Actuator--ON/OFF: This data refers to the state of the suspension damper solenoid contained within the shock absorber.

LF Position Sensor--Range 0.25-4.75 volts: This data refers to the vehicle height measured in volts.

LR Position Sensor--Range 0.25-4.75 volts: This data refers to the vehicle height measured in volts.

Marker Pulse--High Low: This data indicates the state of marker pulse in the steering wheel position sensor.

Rear Leveling Air Pressure, if equipped -- psi/kpa: This data indicates the system pressure in psi.

Rear Leveling Air Pressure, if equipped -- Volts: This data indicates the system pressure in volts.

Right Front Damper Actuator--ON/OFF: This data refers to the state of the suspension damper solenoid contained within the shock absorber.

Right Rear Damper Actuator--ON/OFF: This data refers to the state of the suspension damper solenoid contained within the shock absorber.

RF Position Sensor--Range 0.25-4.75 volts: This data refers to the vehicle height measured in volts.

RR Position Sensor--Range 0.25-4.75 volts: This data refers to the vehicle height measured in volts.

Sensor Supply Voltage -- Volts: This data indicates the voltage being supplied to the sensors from the ESC module.

Vehicle Speed -- Range --193 km/h (0-120 mph): This is the ESC module measurement of the vehicle's speed from a discrete output from the powertrain control module (PCM).