C0665 Code: Meaning, Causes, and Symptoms | OBD2 Codes
C0665 – Level Control Compressor Relay Malfunction
C0665 Possible Symptoms
Anti-Lock Brake System (ABS) Warning Light ON,Engine Light ON (or Service Engine Soon Warning Light)
C0665 Possible Causes
Faulty Level Control Compressor Relay,Level Control Compressor Relay harness is open or shorted,Level Control Compressor Relay circuit poor electrical connection
The Electronic Suspension Control (ESC) module monitors a lift/dive signal at the Powertrain Control Module (PCM). Under normal conditions, the ESC module supplies a 5-volt reference voltage to the PCM. The PCM grounds this circuit when the vehicle is accelerating rapidly (LIFT) or braking hard (DIVE). When the lift/dive signal goes low (approximately 0-volts), the ESC module commands all four ESC dampers to a FIRM condition.