Code S036, ELC Compressor Short To Ground/Open: Description

Leveling errors are detected via a single error feedback signal from a 4-channel integrated circuit (QDM) which drives the compressor relay and the exhaust solenoid. The RSS module monitors this discrete feedback through all 4 possible leveling states and decodes it only if all 4 states have been seen. Leveling states include:

• Compressor OFF, Exhaust OFF
• Compressor OFF, Exhaust ON
• Compressor ON, Exhaust OFF
• Compressor ON, Exhaust ON.

All 4 states occur shortly after every ignition ON cycle when the leveling system goes through an air replenishment cycle, as well as during normal operation. Only electrical problems with the compressor relay will be flagged.

The default mode for the relay is normally open with zero current so no compressor operation occurs. Compressor motor problems and pneumatic leakage problems will not set a code, but the RSS module will shut the compressor off if no progress is made or if excessive run time occurs.

1. See NOTES ON INTERMITTENTS  under TESTING & DIAGNOSIS.
2. A temporary compressor overload (i.e., high head pressure during a cold start) may cause the fuse to blow.

Fig 1: Code S036 - ELC Compressor Short to Ground/Open (1 of 2)

Courtesy of GENERAL MOTORS CORP.

Fig 2: Code S036 - ELC Compressor Short to Ground/Open (2 of 2)

Courtesy of GENERAL MOTORS CORP.