GM Service Manual Online
For 1990-2009 cars only

A scan tool may be used in order to command the strut or shock absorber solenoids ON or OFF, without the need for input information from other components. This can be very helpful in determining if a certain portion of a circuit or a component is in working order. The table below lists the tests that are available for the Electronic Suspension Control (ESC) system. The tests are listed in alphabetical order.

Using a scan tool, select the ESC Special Functions from the scan tool menu. The status of the output being cycled will be shown on the scan tool's display screen. The solenoids on the struts or shock absorbers can be cycled to turn ON or OFF by selecting Damper Actuator Test under Special Functions on the scan tool.

Using the LF shock absorber solenoid as an example, commanding the LF shock absorber solenoid ON can indicate whether the ESC system is able to correctly operate the LF shock absorber solenoid. This can determine if a DTC that pertains to that shock absorber solenoid is able to reset, and if the ESC module's internal circuitry is able to operate the LF shock absorber solenoid. For example, suppose the ESC system sets an intermittent DTC C0577. This DTC is the LF Shock Absorber Solenoid Short to Ground. In order to diagnose this condition using a scan tool, select the ESC Damper Actuator Test under Special Functions on the scan tool. Then, cycle the LF shock absorber solenoid while moving the suspected wiring/connector. Attempt to duplicate the malfunction conditions. This scan tool feature allows checks that could not be performed while driving the vehicle. This example can be applied to the other shock absorbers solenoids.

Also, the ESC module can be recalibrated using a scan tool. Select Recalibration function from the scan tool menu. Although the ESC recalibration function is not under Special Functions it is included with the rest of the information in the scan tool output controls table.

Scan Tool Output Controls

Scan Tool Output Control

Additional Menu Selection(s)

Description

Damper Actuator Test

LF Damper Actuator

Commands the left front strut solenoid ON and OFF.

Damper Actuator Test

LR Damper Actuator

Commands the left rear shock solenoid ON and OFF.

Damper Actuator Test

RF Damper Actuator

Commands the right front strut solenoid ON and OFF.

Damper Actuator Test

RR Damper Actuator

Commands the right rear shock solenoid ON and OFF.

Damper Actuator Test

Select All Dampers

Commands all the solenoids ON and OFF.

Normal Force Test

LF Normal Force

Commands the left front force percentage sent to the EBCM.

Normal Force Test

RF Normal Force

Commands the right front force percentage sent to the EBCM.

Recalibration

Recalibration

Commands the recalibration of the ESC module after installation.