Code S013, Left Front Damper Solenoid Short Across Load: Description

To produce a soft damper setting, solenoid high side is switched to battery voltage to allow solenoid to move to open position. After this initial pull in, high side of solenoid is pulse width modulated to hold valve in open state while reducing current draw.

Finally, this switch is turned off to close valve. This produces a firm damper setting. The firm mode is produced with an OFF state, and soft mode is produced by a combination of boost and hold states.

The soft and firm settings toggle based on various road conditions to provide optimal ride and handling.

Shorts across solenoid are detected by a high side and low side feedback signal connected to damper drive and damper return line. The RSS module monitors these discrete feedbacks through all possible states (On, Off, PWM High State, and PWM Low State).

Since a short across load is destructive to high side circuitry, error detection quickly yields a firm damper setting, and a cool-down time is allotted before another attempt is made to drive solenoid. Multiple attempts are required to supply filtering to avoid false errors from being detected.

If a specific number of consecutive errors occurs, all 4 dampers are set to firm for remainder of ignition cycle. The default mode for damper solenoid is closed to produce a firm damping level when no current is applied.

1. See NOTES ON INTERMITTENTS  under TESTING & DIAGNOSIS.
2. A short to battery in circuit No. 1107 or a short to ground in circuit No. 1113 may damage windings in solenoid and create an open.

Fig 1: Left Front Damper Solenoid Short Across Load (1 of 3)

Courtesy of GENERAL MOTORS CORP.

Fig 2: Left Front Damper Solenoid Short Across Load (2 of 3)

Courtesy of GENERAL MOTORS CORP.

Fig 3: Left Front Damper Solenoid Short Across Load (3 of 3)

Courtesy of GENERAL MOTORS CORP.