Road Sensing Suspension (RSS)

CIRCUIT DESCRIPTION
To produce a soft damper setting, the damper's drive line is switched to battery voltage to allow the valve to move to the open position. After this initial pull-in, the drive line is then pulse-width modulated (PWM) to hold the valve in the open state. Finally, the drive line is removed from battery voltage to place the valve into a closed position which produces a firm damper setting. The damper's soft and firm settings toggle based on various road conditions in order to provide optimal ride and handling.

The RSS module monitors all four damper's solenoid drive and return lines during the "OFF," "ON," and PWM command.

RS0016 WILL SET WHEN
1. If the RSS module senses the drive line low and the return line low for three consecutive samples during an "ON" command, a code will set.
2. Or, if the RSS module senses the drive line low and the return line low for three consecutive samples during a PWM high state command, a code will set.
3. Or, if the RSS module senses the drive line high and the return line low during the 5 to 20 mS portion of the "ON" command and also does not sense the drive line high and the return line high during the "OFF" command, a code will set.

ACTION TAKEN
For a drive line short to ground, the RSS control module will stop driving all four damper solenoids. For a return line short to ground, the RSS control module will stop driving only the affected damper solenoid. The module will then wait 5 seconds, attempt driving the solenoid again, and sense the drive and return lines. If the fault is not present, the RSS module resumes normal operation. Otherwise, it will repeat the stop-wait-retry-sense sequence. A software counter is incremented for each fault observed or decremented for each fault not observed. If the counter reaches three counts at any time, the solenoid is de-energized for the remainder of the ignition cycle, a code is set, and the "SERVICE RIDE CONTROL" message is displayed.

RS0016 WILL GO "HISTORY" WHEN
1. The RSS module senses the drive line low and the return line high during the "OFF" and the PWM low state commands.
2. The RSS module senses the drive line high and the return line low during PWM high state command.

NOTES ON FAULT TREE
1. Refer to Intermittents And Poor Connections. Diagnostic Aids
2. Refer to Clearing Diagnostic Trouble Codes. Clearing Diagnostic Trouble Codes

DIAGNOSTIC AIDS
History codes are used to help diagnose intermittent fault conditions and do not necessarily indicate a faulty RSS module. The RSS module itself is a reliable component and is not likely the cause of the malfunction. Most system complaints are linked to faulty wiring and connectors and, occasionally, components. Performing a thorough inspection of all related wiring and connectors pertaining to the history code stored will reduce diagnostic time and prevent unnecessary part replacement. If the problem is intermittent, try performing the tests shown while "wiggling" wiring and connectors. This can often cause the malfunction to appear. Check for poor connections at both the RSS module and the related components. These could cause an open, short, or an intermittent malfunction. Refer to Intermittents And Poor Connections. Diagnostic Aids

IMPORTANT
^ Do not backprobe sensors, dampers, electronic leveling control (ECL) connectors, or SSS connectors.
^ When all diagnosis and repairs are complete, clear codes and verify operation.