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Road Sensing Suspension (RSS)









CIRCUIT DESCRIPTION
The RSS module detects leveling faults via a single feedback signal (on the low side of the exhaust solenoid) from solid-state drivers (internal to the RSS module) which drives both the compressor relay and the exhaust solenoid. The RSS module monitors this feedback signal through all four possible leveling states (OFF, EXHAUST, COMPRESS, and a state in which the compressor and exhaust are both on) and decodes it only when all four states have been seen. All four states occur slightly after every ignition-on cycle as well as during normal operation. The default mode for the exhaust solenoid is off so no exhaust occurs.

NOTE
Only electrical problems with the exhaust valve will be flagged. Compressor motor problems and pneumatic leaks will not set a code, but the RSS module will shut the exhaust function off if no progress is made or if excessive run time occurs.

RS0037 WILL SET WHEN
The RSS module senses the feedback high during an "ON" state and appropriate decoding has occurred.

ACTION TAKEN
The RSS module will log a RSOO37 code and will disable all Electronic Leveling Control (ECL) functions for the remainder of the ignition cycle.

RS0037 WILL GO "HISTORY" WHEN
The RSS module senses correct operation after an ignition cycle.

NOTES ON FAULT TREE
1. Refer to NOTES ON Intermittents And Poor Connections.
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.