Code S012, Left Front Damper Solenoid Open Circuit: 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.

Solenoid open circuit errors 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 an open circuit is not destructive to circuitry in RSS module, an error is detected but solenoid continues to be driven based on road inputs. 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: Code S012 - Left Front Damper Solenoid Open Circuit (1 of 2)

Courtesy of GENERAL MOTORS CORP.

Fig 2: Code S012 - Left Front Damper Solenoid Open Circuit (2 of 2)

Courtesy of GENERAL MOTORS CORP.