Code S012 - Left Front Damper Solenoid Open Circuit: Description

Solenoid open circuit errors are detected via 2 error signals that are on both sides of the load and follow a high side switch. This switch is turned on continuously to quickly boost the valve open. This produces a soft damper setting.

After this initial pull-in, the switch is pulse width modulated to hold the valve open with little power dissipation. This maintains the damper in the soft setting. Finally, this switch is turned off to close the valve. This produces a firm damper setting. The firm mode is produced with an OFF state, and the 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. The RSS module monitors these discrete feedbacks through all 3 possible states and at both high and low levels of the hold PWM state.

Since an open circuit is not destructive to the circuitry in the RSS module, an error is detected but the solenoid continues to be driven based on road inputs. The default mode for the damper solenoid is closed to produce a firm damping level when no current is applied.